OneOfThoseQueers
It'd been 2 weeks, 3 days, and 6 hours since Will had given the painting to Mike. 2 weeks, 3 days, and 6 hours since Will had lied about the painting to Mike. After he'd done it, poured his heart out to him in what was essentially a long overdue confession, there had been a bomb ticking in the back of his head. He knew, eventually, the bomb would go off, and he'd be found out. Mike, despite being oblivious as all hell, was not stupid. Will knew that at some point, he'd put the pieces together. He just hadn't expected it to be so soon.
Or
Mike confronts Will about the painting, and after a long overdue conversation about their feelings, Mike reveals something he's been hiding from Will.