Your're coming to this strongly they're both idiots, and that set up the misunderstanding, ml thought the mc remembered they slept together and didn't bother clearing it up also he's not aware of the many complications mc has, mc doesn't have awareness to be suspicious of ml's actions and also "strong-will"s his way through his complications.
Idk what kind of cute story you're expecting, but I'm having fun with this plot

Not only did the very much sober ml sleep with the shit faced mc(rape), he didn’t spell it out that they had a one night stand.
He was just talking long and beating around the bush.