And so if Malice is one half, what happened to the rest of Adrian?

Well without certain members of his makeup, the powerbalance within his identities and thus appearance shifts. He's still on the curvy side, though shorter, and missing his gigantic ears. He looks much more like a certain other triplet instead, due to most of the asexual components shifting to Malice and thus leaving Katsuu's hypersexual ass out of balance :D
It's caused him to become more active, more playful, and a little more promiscuous, though he still holds himself back, if only a little.
This pup has issues and is more than happy to share them with you~
Overall though, the pair of them are still out of balance, and really shouldn't be kept seperate for long.