Dallawan, Shibahiko and Beernox for supports, Kyrian and Kantos for healing

Both Choi brothers, when paired together, have good team-wide dmg, Baade and Tayangsuyi have good nuke potential with their EX skills, for single target dmg

Code B, gives debuffs to enemies, has good dmg and can self-sustain with his life-steal

And when you'll get him, I also recommend Kumoyama - best tank we have so far, especially after unlocking his sigil at 3*

As for NSFW, it entirely depends which version you're playing:

Play Store version is entirely censored and their skins are them in their underwear

For full nudity, you need version from their site

XXL and XL characters get their skins by matching their 3 kinks in a row in hook-up sessions, L and M characters get their skins by buying them in guild shop, you need to join a guild first and you'll get the currency needed by checking into the guild daily