So... basically she shlicks in his room and is surprised that he comes home after work - to his room! Hentai tropes are the best...
By the way: †žShe is acting like my girlfriend“ - be honest with yourself, male tsundere...
That title and the Vanilla tag...Hmm, rather intriguing.
Ah yes, catching her masturbating to his videos, all while commentating about how she tried changing herself for him while he's right there.
And of course, the 'pretend to be a slut and provoke him' plan. Worked out perfect, and the sweet Vanilla loving that resulted is quite nice indeed.
Great ending though. "I guess my new lifestyle isn't all that bad"? I'd say! You have a cute girlfriend who brings you lunch while you're at work...Not bad is kind of an understatement.
Well, on the assumption that Landlord/Daddy approves their union, at least one thing Takahiro can start doing is to divert rent money into other areas, probably in preparation for when Ichika graduates.
By the way: †žShe is acting like my girlfriend“ - be honest with yourself, male tsundere...