The dog as you can play fetch. Other than that Astarion has a pretty macabre personallity and gives you the thumbs up everytime you do something diabolical. Lae'zel is linear and annoying, shadowheart is better since the patch and Gale is pretty fun.
On a side note the voice acting across the entire game is top notch. Just compare it to AAA gems like Woke Effect Andromeda and my face gets tired.
