I, Ranna Fujii, Who Was Kept Under House Arrest By A Sex-crazed Old Monster Who Lived In The Garbage Room Next Door, And Was Forced To Cum Inside Her Without Escaping

Ranran, a devoted and beautiful girl who just started living with her boyfriend. What bothers her a little is a man in his 60s she often sees in the common areas of his apartment building—a scary-looking neighbor who doesn't return her greetings and stares at her like he's licking her. One day when her boyfriend is away, she hears loud moaning from next door. To protect her happy life with him, she musters up the courage to go complain, but the neighbor answers the door in his underwear...