I think this is severely under explained. The whole reason as to why Dojae even did that was because he didn't know. He doesn't understand empathy and lives life logically. To him, they were not dating and thus didn't have to be exclusive. Everything is explained so wonderfully. Their relationship is so realistic, it's a great read.
Wrong. Dojae says “I’ll only be with you” while they do their limited dates. So he lied regardless of his understanding for their relationship. He knew MC loved him but still slept around, he knew he wanted more with MC but still let him leave after breaking his heart, then he tries to move on with a new guy IMMEDIATELY after. And MC still goes crawling back to him… it’s pathetic
The story very clearly outlines that he feels emotions different than others and doesn't understand his own very well. Dojae appears to be autistic, he is consitently struggling throughout the relationship even when they aren't fighting.
Dojae made a massive change in character and learned to respect Euntak's boundaries. Also remember he didn't kiss that freshman until after he saw Euntak cozying up with Hyuk and got the wrong idea. He came clean later, and never hid it.

Bro I love this type of story, but Dojae didn’t suffer enough. Bro didn’t even grovel, MC just folded immediately. Dojae literally slept around after saying he would only date MC and that just doesn’t get brought up directly. Just the one time he was caught kissing some freshman girl. DOJAE LITERALLY FOUND A NEW GUY ASAP AFTER THEIR FINAL DATE. and MC took him back LMAO. Bro grow a back bone.