rukiamara's manga / #Rape(110)

I don't understand the whole concept, how Tsuji is treated like love rival out of nowhere here?! He sexualy abused Mimori, forced him twice, telling Mimori it's his fault! Mimori never considered him as potential partner, it was Yuma from the beggining, and here we have Tsuji, who is treated as someone who has a chance to win Mimori's heart....what?! And Yuma and Mimori behave like they need to prove their love to him...this is insane, where did it come from?! ヽ(`Д´)ﾉ