bonds, Su Li. an oriental witch might know some useful things for him to learn.
also, have him bond a vampire, a shortcut to their power.
slaves:
belatrix le strange, narcissa malfoy.
theyre hot, sisters, and it removes 2 large potential threats. noone wants to fight bella, and narcissa can claim the malfoy fortune away from her husband and leave the dark side fund less.
maby even bond bellatrix, she is fanatically devoted to voldemord, with the sacred bond she will replace the dark dork with harry, giving him access to a trainer of dark arts, and a large as shit magical core to draw from.