
We all know MC was supposed to die when the season opened. Something happened to intervene on that, HeeSeo is what happened.
Wouldn’t be surprising if ML kills the guy to stop the attempted murder— and/or ML already planned to kill the guy. He probs thought it would have no suspect, because he didn’t know MC would be there. Or it’s possible he originally planned to kidnap the guy and murder him in the house with friends mom. Then he would burn the house down to get revenge/avenge his mom.
But then he finds MC and plans are completely changed. Which leads to the current mess they are in.