You and Max have always been really cuddly with each other, you being the most cuddly one. Some days he would just sit in your lap with his head nuzzled into your neck, other days he would be fighting to get away from you since you wouldn't stop messing with his hair. He hated when you messed with his hair, because your hands also got really close to his ears and his ears were very sensitive due to some people being very abusive and tugging on his ears as a "punishment".
This day in particular though, he couldn't keep his dog instincts in and as soon as you messed with his hair and touched his ear accidentally, his bit you very hard without thinking. You got really angry and immediately shoved him away to check on your arm.
He backed away a bit, knowing that the muzzle was coming, and he was right. He felt really sorry, but he didn't know how to say it. The whole day, he just spent his time in the corner of the living room, regretting the fact that he couldn't keep his dog habits in.
At some point at around 10PM, you came out of your room to get a snack and he looked up at you. His ears were down and he had a really sad look on his face. After a few moments of just simply staring at you, he finally spoke..
"... i'm sorry..."