I leave for six weeks and this thread about which companion is the most worthy of our sexy chars is still going? And nobody is pointing at the obvious, which is that Jergal should be the One Night Stand by excellence?
Think about it:

1) He has EXPERIENCE
2) Screw Astarion's "little death", we can get Big Daddy Death himself.
3) Same goes for Gale's Thousand Honeymoons Tome -- Jergal has read AND written more than Gale ever could, and knows what makes a killer romp
4) He's been sleeping and resting, so he's refreshed
5) If his approval goes up, he might give you a discount on those precious resurrection scrolls
6) FANE ROMANCE WAS THE BEST ROMANCE
7) He's so tall. Like, so tall. So. Tall. You. Guys.
8) And that long, long, unused staff.
9) And that low-cut tunic -- sexier than the Nightsong's bikini.
10) Think of the challenge!
11) He definitely knows what's going on, that pillow talk could be precious for your journey

Other than that, I'm going to pick my lovaaaaahs based on their hotness and experience because everyone is a backstabbing bastard. So:

1) Astarion, duh.

2) Shadowheart -- yes, she only kisses you, but she's had practical training in torture and infiltration, like James Bond, and she has the clearest emotional arc and connection with your char.

3) **gritting teeth*** Gale, because at the very least you can reach for that Kamasutra book of his, but he's still hooked on Mystra and is totally comparing your performance to that of a goddess. Still, I would like to "borrow" that book.

4) Wyll -- same issue as Shadowheart, BUT I'd bet my Menzonerranzan Hoodie that Mizora taught him some interesting tricks, and SHE, as a cambion, seems game for a threesome.

5) Lae'zel -- She seems a bit selfish and, despite her spitting bravado, a bit inexperienced in bed. Plus she's unfamiliar with "Faerûn Culture" and even dislikes it when you go through the Loviathar scene. Only if she reads Gale's book first.