Sayotsugu

Sayotsugu is the femslash ship between Sayo Hikawa and Tsugumi Hazawa from the BanG Dream! fandom.

Canon
Sayo is the guitarist of Roselia while Tsugumi is the keyboardist of Afterglow. Other than being from rivaling bands, they are also associated with each other through Hina Hikawa, who happens to be Sayo's twin sister and the student council president of Tsugumi's high school. Although the two had never crossed paths prior to the "Cooking Class Craziness!" event, nor did they have a particular reason to interact, both Sayo and Tsugumi have come to be good friends.

Sayo is a more serious and closed-off individual, while Tsugumi is optimistic and earnest. However, the differences in them are successfully balanced out by their shared hard-working nature, giving them complementary yet harmonious personalities.

Cooking Class Craziness!
This is the first event featuring Sayo and Tsugumi as the main focus. Through a poster outside the shop, Sayo was informed that Hazawa Coffee would be hosting a cookie-baking class, during which Tsugumi got assigned the role of a helper. Due to the image she had of her, Tsugumi was surprised to see that Sayo had showed cooking class that day. Although nervous at first, Tsugumi endured helping Sayo, who appeared to be struggling, to follow the instructions and successfully bake the cookies. The two unexpectedly discovered their common characteristics through the cooking class.

Spring Arrival Chocolate Roll Cake
Introduced in February 2022, Spring Arrival Chocolate Roll Cake was an event curated in time for Valentine's Day. The story begins with Sayo and Tsugumi talking about their Valentine's Day plans. Tsugumi mentions feeling stuck on what to do for Afterglow, prompting Sayo to bring up a novel about a special chocolate roll cake and 2 friends who regularly hang out to eat desserts together. Tsugumi tells Sayo that she would like to visit the town referenced in the novel in order to go to its café and try the cake that was created in honor of the book. Sayo asks Tsugumi if she would like to go there with her, to which she agrees, feeling flustered due to the unexpected offer.

On the day of the meet-up, they decide to tour the town before going to the café. At the near end of their tour, Tsugumi mentions wanting to go to the town's park but is afraid the time restriction would not allow them to; however, Sayo reassures her that there was time and that they should go there since it was such a significant location in the novel. Upon their arrival to the park, they were amazed by the sight of the snowdrop flower field, to which they referenced a scene in the novel where the protagonist received a bookmark pressed with the flower. Tsugumi mentions that this flower is traditionally exchanged on Valentine's Day in Europe. When they have made their way back from the park to visit the café, they were surprised to find out that it was closed for the day.

Since they were unable to eat the cake at that town, Tsugumi suggested that they should make the chocolate roll cake together at Hazawa Coffee one day instead, to which they did. As they were cleaning up after their baking session, the two reflected on their experience, talking about how they are now inspired on what to give Afterglow and Roselia on Valentine's Day. Sayo brings up about how her experiences will help her to refine her own "sound", of which Tsugumi then asks Sayo about whether she has found it or not. The pair continues to discuss this. Approaching the end of the clean-up, Sayo gives Tsugumi a bookmark made with pressed snowdrop flowers like the one in the novel, which caught her by surprise. Tsugumi thanks her for the gift and offers to give something in return.

Hazawa Tsugumi - Afternoon Coffee (Memorial Episode: A Day in Hazawa Coffee)
Sayo comes to Tsugumi's cafe to return a book she lent her and have a cup of coffee. During their exchange, it is apparent that both of them have become very good friends who even learned to understand each other's tastes and thinking in literature. So much so that the girls coincidentally recommends each other the same book, thinking that the other would be interested in reading it.

In one of the dialogues, Sayo also mentions that she thinks Tsugumi is the kind of person who can detect beauty even in people the rest of the world ignores. This is quite a significant detail, as in the past, Sayo often felt an inferiority complex due to Hina's talents and even became an obsessive perfectionist because of it.

Sayo Hikawa - Walk in Early Spring (Episode: Conclusions About The Trip)
Sayo and Tsugumi takes an unplanned trip to the ocean on their way back home from the town. They share their thoughts on the visit and thank each other for the time spent. Since Tsugumi noticed that there were not many pictures of them together during the town visit, she suggests that they should take one at this ocean as a memorandum.

Additional Content
In 2019, Tsugumi was one of the few characters who received a separate congratulatory animation in the twins' birthday lounge. This is noteworthy, as lounge-room birthday interactions only occur between characters who are fairly close in the lore, or ones who have had significant events together within the past year.

According to one of the limited New Year's Eve interactions at the end of 2020, there was an exchange where Tsugumi invited Sayo to attend her New Year's Eve party, also promising her special coffee and cookies.

Fanon
Despite not having much canon content outside of the "Cooking Class Craziness!" event, Sayotsugu is still one of the most popular ships among fans and especially in the Western fandom. This may be due to the fact that both characters come from 5-member bands where the other four are often paired up (those being MocaRan, Tomohima, Yukilisa, Rinako), so naturally, fans became curious about their interactions as the "odd-ones-out" of the groups. Fans were surprised by their unexpectedly warm and harmonious dynamic that was first introduced in the "Cooking Class Craziness!" event, which is also a big contributing factor to Sayotsugu's popularity, given that Sayo is not one to open up easily. It is also the most written ship in both of the BanG Dream! tags on AO3.

While this ship was originally considered something of a running gag in fandom due to little character interaction, it has subsequently received some attention from Craftegg both as a desire to tease popular pairings and as of some their attempt to to divert fans' attention away from romantically shipping SayoHina due to its incestuous nature. For instance, Sayotsugu was teased on a live show episode by Otsuka Sae (Tae's seiyuu) when Sayo's seiyuu, Kudou Haruka, chose Tsugumi as the one she would like to marry amongst all other Garupa characters. This ship has consistently received some minor in-game attention since 2019, either emphasizing the characters' friendly casual interactions or their positive mention of each other in dialogue. So far, their biggest interaction outside of the aforementioned event is the release of the 2022 Valentine's Day event, Spring Arrival Chocolate Roll Cake.

Tsugumi also began to get more interactions with Sayo's sister, Hina, or even both twins together. Consequently, certain part of the fanbase has began to ship all three as a poly ship or joke about a sibling love-triangle. This triad received attention from Craftegg as well. As a result, it is mentioned that Tsumugi "has a special effect on Hikawa twins" in one of the events.

The ship is often rivaled by other popular Sayo ships, such as Sayolisa, Yukisayo and Sayohina. Sayotsugu fans' rivalry with the latter is especially infamous, as both ships are the most popular ships for Sayo and two of the most popular ships in the fandom in general. Thus, Sayohina fans often accuse the latter of having a toxic fanbase, overestimating the potential of their ship and reducing Tsugumi's character and motivations to being nothing but Sayo's girlfriend, while Sayotsugu fans can be found calling out Sayohina shippers for promoting incest and sexualizing the twins' relationship. In some cases Sayotsugu shippers have also harassed and sent death threats to Sayohina shippers, which has soured a lot of peoples' opinion of Sayotsugu, or even caused them to ship Sayohina out of spite. One of the biggest examples for this type of behavior happened when an user named "tsuugusayo" started spamming the comment sections for most, if not all Sayohina fanfics in AO3 with lyrics of certain BanG Dream! songs in August 2020, and event went as far spamming 10 fanfictions in the same tag, with all of the fics being filled with nothing but death threats and insults and flaunting how much superior Sayotsugu is.

Fandom
FAN FICTION

PIXIV

Trivia

 * The pair is often compared to mint chocolate because of their hair colors.
 * Sayo is 161 cm tall while Tsugumi is 156 cm.
 * Upon their first notable interaction, Sayo addressed Tsugumi by "Hazawa-san", but a more recent area conversation shows her addressing Tsugumi by her first name instead (although still keeping the -san honorific)
 * Sayotsugu's alternate ship name "342g" is a play on words with their names (3 - "Sa", 4 - "Yo", 2 - "Tsu", g - "Gu").
 * Sayotsugu is the only cross-band pairing where both girls don't havу major ships or a canonical best friend within their own groups.
 * Tsugumi is the second character after Hina who usually appears alongside Sayo when she is shown standing and/or talking to someone in the background in various additional content.

Variations

 * Sayotsuguhina refers to the ship between Sayo Hikawa, Hina and Tsugumi