Jace had been about to answer Alec when he heard that slamming door and knew - Mark had overheard them and judging by that reaction he didn't like what he'd heard. He wondered how much of the conversation their boyfriend had overheard. It looked like it was time for him to go talk to him. Maybe he should have asked Alec to get Mark to come too. But it was too late for that now. He made his way slowly towards Mark's room, pausing with his hand ready to knock to turn and look back towards his room to see if Alec had followed him.
"Mark? Babe can I come in?" he asked, knocking on his door and waiting for a response before going in. Even if a part of him was saying to hell with being nice - he needed to be in that room now trying to fix this.