Btw the easiest way to skyrocket your approval with Astarion is to rest immediately after talking to Nettie in druid’s grove (sleep cut scene should be him sneaking away) (and head straight there after picking up companions) then finding the boar he drained and sleep again (this unlocks his bite scene– note that’s this will get pushed back in favor of Wyll’s scene with Mizora if you find Karlach the same day). He has a better response if you cut him off early. After that find the monster hunter near the hag’s hut and let Astarion kill him. Assuming you picked up some stray approval along the way (tell Lae'zel to say ‘please’ when rescuing her, recruit Karlach, say you won’t take Raphael’s deal, 'disturb’ the bugbear and ogre, insult and fight the goblins at blighted village, throw shit at the other set of goblins outside their camp, let the tiefling kill Sazza the goblin, just to name a few) and this pixel man’s approval should be high by day three or four of adventuring. This also means he’ll ask to sleep with you before the tiefling party and you can get more approval from agreeing to meet him, playing coy, and letting him bite you again.
You do not need to be mean to children I promise you. I know it says he approves but that’s like a +1 modifier. Accepting his vampirism, playing along when he asks you who you would drink at camp or how you want to die (indulge this man’s morbid curiosity), and standing by his side against hunters nets like +50 when alls said and done. Oh, and camp often.