Generally speaking, all the humus I have encountered are pretty tame compared to some of their cousins. They also stay a bit smaller. Keep in mind that humus (while generally coral safe) will make mincemeat out of your clean-up crew. For the reef setting, go with one of the Xanthichthys triggers. They are incredibly mild-mannered, perfect sized for a 100g, and they can be paired up.
If you wanna go with the humu, your very limited as to what you can keep. Humus may re-arrange your rock work and damage your SPS corals, some good choices for tank mates would be large clowns, dwarf angels, damsels, and small eels.