the only characters you need to show off in the brothel are Wonder Woman, Supergirl and Hawkgirl. Each of htem can trigger a scene with Lobo, and after you got all 3, you unlock him as a hireable character, trying to work of his debt. After a few heists, he offers you Crush in exchange.Can I avoid prostitution and sharing? Or will I miss out on most of the content if I do so?
Iirc Batgirl can trigger a scene there as well, if you have Poison Ivy stationed at the Meta Bordello...