In a surprising twist that I think no one saw comming from early access, Astarion and Halsin are like totally opposite ends of whatever gay motherfucker spectrum theyre on
Astarion presents himself as alluring, flirty, desirable, sexually available, ect ect, but it's entitely preformative. If given a choice he'd happily go without it all for as long as he can.
Meanwhile Halsin is the most regular, sober, sensible dude ever who probably smells like damp leaves and dirt, and then he just show up one night like "i wanna fuck nasty like the oak father intended"