SouMako

SouMako is the slash ship between Sousuke Yamazaki and Makoto Tachibana from the Free! fandom.

Eternal Summer
The two interact very little in the series. Their first real one on one interaction is in the OVA when they discuss Nagisa's ability to coerce people into doing what he wants and when they battle each other briefly during the water gun fight.

Dive to the Future
FIRST SWIM IN ANOTHER COUNTRY

One of Makoto’s friends asks if he wants to meet up with one of their friends after lunch. Makoto says he can’t, since he has other plans. Makoto’s plans turn out to be calling Sousuke. Sousuke asks if Nagisa told Makoto about Ikuya, Makoto says yes. Sousuke tells him that he had seen Ikuya IM before, but he doesn’t know anything else. He asks Makoto if something was going on with Ikuya, but Makoto only knows that Haru had talked to him, and he seems to have changed a lot since their swim team days in middle school. Sousuke realizes that Ikuya was an old teammate.

Fanon
What originally started as a seeming "crack" ship grew to have quite a large fan base despite it being considered a "rare" pair. Ever since Eternal Summer's ending, the pair grew a large number of followers of all kinds, and not just ones that ship RinHaru, showing the ships appeal to numerous different people.

Souske and Makoto tend to serve as a second focus couple in RinHaru fics. However, due to the ships soaring popularity, the pair have numerous fics dedicated to them and only them, and are not just a secondary to RinHaru fics.

Some of the reasons people ship them is because of their opposing personalities (Sousuke being slightly intimidating and the dark-broody type, while Makoto is the easy-going, friendly type). Thus, the two's personalities are seen complementing each other, playing off of their strengths and weaknesses. The fact that both of them are also currently not going into competitive swimming and that each of their best friends are friends with each other makes it easy to imagine them hanging around each other and building up a relationship.

On AO3 it is both Sosuke and Makoto's second largest ship. It is the fifth largest pairing in the Free! tag.

Fandom
AO3

Tumblr

Trivia

 * Makoto's animal is a killer whale/orca while Sousuke's is a whale shark.
 * Makoto main stroke is backstroke.
 * Sousuke's main stroke is butterfly.