Both Toko and her alter, Jack, possess an extreme obsession with Byakuya, who regards their crush as disturbing.
Toko finds Byakuya attractive. She can often be seen blushing when he addresses her and misinterprets his disgusted remarks about her “stench” to be concern. She hopes to one day assume an affectionate relationship with him, but is content with him constantly insulting her for now, seeing his genuine dislike of her as mere “lovers' quarrels”. The two are frequently either seen together or noted to be absent from the group, although this is largely due to Toko's tendency to stalk Byakuya.
On the other hand, Jack insulted Byakuya at first, who was very surprised as a result. However, Jack found Byakuya attractive as well and declared in a Free Time Event that Byakuya was the only cute "boy" she wouldn't kill as she wanted more than just a “physical” relationship with him.
Like Toko, Jack is usually seen stalking Byakuya and following him everywhere. Byakuya generally harbors animosity toward her in return, but this side to their relationship eventually evens out into simple apathy. While Byakuya actively avoids Jack by hiding in the boys' changing room and insisting they aren't together, he usually does not put in the same effort with Toko and will simply tell her to go away if he doesn't want her nearby. Toko and Byakuya even managed to have several conversations that could be classified as normal, despite Jack's existence. After Sakura's trial where he learned to not underestimate or treat other people's feelings lightly, he compliments Toko on finding a knife.
In the Bad Ending for the first game, it is suggested that Byakuya may come around to care for Toko with time or that he might harbor some feelings for her, as he is holding her portrait to include her in the image and is smiling as he does so. However, given his aversion to these sorts of feelings, it is unlikely he would be open to these sorts of feelings for a long time.
In the second game, Kyoko mentioned that “someone” was waiting for him to go back, meaning Toko is still obsessed with him.
He seems to have a secret sense that tells him when either Toko or Jack is having a perverted fantasy about him. He also maintains contact with Komaru and Toko after Ultra Despair Girls and is able to call them in their hotel room.
In an interview, it was revealed that Byakuya would have gone with Makoto to collect Komaru and Toko from Towa City.
In the Danganronpa V3 bonus mode Ultimate Talent Development Plan, her attraction to him is almost psychotic, she, very openly, stated that was turned on by the thought of being his doormat.
- “If it's wh-what Master wants, I'd do anything h-he asks.”
- — Toko ready to do anything for Byakuya, in Chapter 4 of Danganronpa: Trigger Happy Havoc.
- “Byakuya said he...l-likes a girl to have some meat o-on her bones, so... I'm g-gonna start eating! I'm gonna force it d-down into my stomach! I'm gonna eat till I d-drop!”
- — Toko decides to eat more for Byakuya.
- “What I share with her isn't just knowledge. She and I also share emotions. If we didn't, there's no way we'd both love Master.”
- — Genocider Jack and Toko sharing their love for Byakuya, as the former says in Chapter 4 of Ultra Despair Girls.
- Toko – “Master and I are rock solid. Even if we're apart, our feeling towards each other will never change.”
- Byakuya – “...Yes, that's correct.”
- Toko – “...Huh? Master Byakuyaaaaaaa!”
- Byakuya – “It's true, what you said. Even if we're apart...My feelings of disgust toward you will never change.”
- — Toko and Byakuya once Byakuya is found in the Epilogue.
- “Fine. I'll partner with you. For just a little while. At least until I've repaid the debt I owe to Toko and your sister.”
- — Byakuya to Makoto in the Epilogue, acknowledging he owes Toko for saving his life.
- “I... I can't lose this battle... Master Byakuya wants my help, and that almost never happens.”
- — Toko in the subbed version of Future Arc's episode 7.
The ship sailed as a result of Toko's canon obsessive attraction to Byakuya. However, it received a mixed reception from the fans. The haters of the ship often wish Toko would stop being obsessed with Byakuya and stand up for herself. Its supporters root for her to eventually win the heart of her beloved and enjoy every little moment when Byakuya is nice to her.
A lot of fans abandoned the ship because of the way Byakuya treats Toko (aside from an occasional moment of "Throw Dog a Bone"). This was especially the case when in Chapter 2 Byakuya exploited Toko's secret of having an alternate personality with a serial killer to frame her during the Class Trial to make things more interesting. The ship has sunk for a lot of fans even more with Ultra Despair Girls giving Toko a best friend with whom she got a much more popular ship.
In fan fictions, their relationship tends to be portrayed like a canon one, Toko gets to win Byakuya's heart or sometimes she ends up losing her interest in him (often for Komaru).
- This ship shares many similarities with Sounia, as both ships feature a perverted person with an obsessive one-sided attraction to a person from a noble family. Both members of both ships also survive their respective killing games.
- They appear together in the opening of Danganronpa: Trigger Happy Havoc, as well as both openings of its anime adaptation, Danganronpa: The Animation.