“My sister...her name is Ximnis.”——On the way back to the hospital, Mio (Rina Kawaei) confessed to Taiga (Mazu Takasugi) about the past, that is, about her sister Yui (Riko Narumi) who lost her life six months ago... and that she was a “ murderer.”’s reason, and why he came to Xingling Medical University as a killer...?

After Mio confessed everything and returned to the dormitory, what awaited her was... her room was in a mess.

It seems that a thief came in while he was away, but for some reason only the "laptop" placed on the table was stolen... During the police investigation, Mio was unable to enter her room, so she stayed one night in Taiga's room next door...

The next day, after learning about Mio's sleepover incident, Harumi (Miki Mizuno) and Natsume (Yoshizumi) were very interested in the exciting development of Mio and Taiga's love.Souma (Yuuma Yamoto), who likes Mio, is very worried.

That night, Mio and his party came to the izakaya, and Soma met his college friend Yuji Naito (Jumi Totsuka).Although Souma and Naito are both taciturn people, they haven't seen each other for two years.After asking, I found out that Naito had broken up with his then-lover Iori (Rina Asakawa).“Why? I obviously like you so much...”. The moment Souma asked why...! Naito suddenly said loudly as if he had changed: “I still like Iori!”.Naito's sudden change surprised Soma...

After a while, Naito came back to his senses and said that he had no memory of screaming.In fact, he has also suddenly changed his mind in the workplace recently and made harsh remarks to his seniors.As a precaution, Naito underwent an examination at Seiryo Medical University, and what awaited him was a shocking examination result...What's the reason for the quiet man's sudden change of temperament...?