Based on this chapter, maybe it's the latter?
From his internal monologue I think he's in love/obsessed with Haesoo, and he's looking to get revenge on her behalf, probably fueled by his own history of abuse and neglect and the mother we still don't know much about.
My theory is he probably sees himself in her and is trying to protect her in a way that will later connect to his mom, either because she protected him or because she didn't, but it's definitely a revenge by proxy imo
Also, Mincheol’s how he got the job thing really interesting.. Everyone in the office questioning that Who is that mystery someone got him the position..
knew it.. Obviously met before and he planed everything.. But i wonder that he’s trying to screw Mincheol.. Or he wants Heeso.. Like what’s the first motive…