The kind senior who lives next door is actually a dangerous person__.

Shionoya Hino attends university.
Kaneto Kanazawa, a senior who is close to Hino and her girlfriend and is secretly interested in her.

After school, Hino and Kaneto decided to go home together.
Kaneto offered Hino some cocoa.
However, the cocoa is loaded with diuretics...

When Hino arrives in front of her girlfriend's house, she realizes that she doesn't have the key.
When she reaches the limit of her patience, Kaneto offers to lend her the restroom.
Hino accepts her proposal. However, there were conditions for renting the toilet.
She ended up saying that she could listen to anything Kaneto said.

"Have sex with me"

Hino has already agreed.
The true nature of the kind Kaneto is revealed__.