"How dare this guy live a lifestyle where he dedicates his entire being to me? I'm going to change his ways so that he'll live a lifestyle where he dedicates his entire being to me!"
Seriously Masaki's already obsessed with Mikatan and he would be her boyfriend if she were to ask him. Especially now that he knows that Mikatan is single. Masaki's otaku ways led him to being a super-fan of Mikatan . If you ask me Masaki being an otaku fanboy of Mikatan is the only reason he's putting up with her crap. I think making him give up the otaku lifestyle will also have the effect of him not wanting to be Mikatan's fan which would in turn lead to him losing his feelings towards Mikatan.
There is no logic with what Mikatan is doing. If this was just her wanting to see Masaki suffer just so she can get her sick kicks, it's dumb as all get out, but I can follow some sort of reasoning. This whole making Masaki regret his otaku ways is not going to lead to him wanting to be Mikatan's boyfriend.