Makoto sees what he thinks is a person drowning only to find out it's a mermaid, Haru, being, erm, molested by an octopus. So Makoto saves the day and takes the mermaid home, only for Haru to tell him that he needs Makoto's superior genes and they should mate. Makoto is taken aback by the sudden proposition, not realizing that he and Haru have met before, and he was the one to make the first move back then. Trigger warning: attempted rape (octopus).
Free! dj - Tadashii Ningyo no Aishikata