"Like when you were smashing my head into the floor of the library or so drunk that you couldn't walk yourself home?" Regulus asked caustically. Just because he had told James about how he had died didn't mean he wanted things to go back to the way they had been between them. The fact of the matter was that the last two times Regulus had run into James, things had gone very poorly for Regulus. The first time he had walked away with bruises on just about every inch on his body and the second time he had woken up on a beach by himself with sand in places he didn't even want to think about.
He wasn't going to let James just woke his way out of this one. He didn't want to go back to sneaking around and worrying about getting caught. It had tested his boundaries when they had done it in school, but it was far too much now. James Potter needed to be told no every now and then. He needed to not get everything he asked for in life.
And Regulus just wanted things to be simpler in his own life. He wanted to get along with Sirius. And Bellatrix. He wanted there to be no war to worry over. And he wanted James to not decide that he owned him every time he saw him.