Di'angelo spinning.
Spinning is supposed coping skill for Di'angelo. He apparently just spins around in a circle on all four feet to calm down. This actually just makes him more upset than he already is. He only does it when he's confused and scared over something. He does it even more when he's gone insane. He usually signals someone that he's going to spin or that he wants to. Not much is known about spinning. Another thing is Di'angelo is apparently hyper enough to spin for hours or even days or doesn't bother him to spin that long. When he chases his tail, this could possibly be a way for him to spin while having fun. He could also have a obsession with spinning or chasing his tail. Once again, this is all unknown. Aza doesn't like when he spins because she believes he'll get hurt and obviously it makes her get upset [along with him]. For Di'angelo to spin for hours on end, he has to concentrate his energy. He has to have a clear mind (whether he's upset or not), and if he has too much stuff in his head he's thinking about, he energy will be lost and he will get tired and stop spinning (often followed by him by him plopping on the floor in exhaustion and/or passing out).