Characters Evolution

All episodes, beside being awesome in themselves, have their fair share of characters interactions that serve the general storyline of the show. Here's what we learn in Pangs.

Buffy: Buffy isn't whiny in this episode. She's the shiny, wacky Buffy we all love. She's okay with getting rid of the demon, as long as it doesn't prevent her to throw her Thanksgiving dinner, which leads to very random and shallow conversations.
Obviously her connection with Angel is still strong, as she starts spazzing any time he's lurking around. Still, we see her relationship with Riley evolve in this episode.

Angel: There's two things about Angel in this episode.
1. He lurks. A lot.
2. He is not evil again.

Xander: He has a new job, the construction job he'll actually keep to the end of the show. We also hear of his previous job, that we'll see again in the dreams of the season finale, Restless.

Anya: Her relationship with Xander takes a great step in this episode. Buffy says they 'seem pretty tight lately', and Xander, though pretending to be delirious, calls her his 'girlfriend'.
She also shows herself true part of the Scooby Gang, helping with the investigation, the fight and most importantly, with the cooking!

Willow: She gets to be the whiny character of the episode. Which may introduce her magical crazyness in the next episode, Something Blue.

Spike: In my opinion, the funniest character of the episode. Every scene he's in is hilarious. Also it's a key episode for him.
First, we have confirmation that the chip prevents him from biting anyone. His career as evil is for now, over. Which will lead him to crash Giles' house and ask the Scoobies for help. This situation will last for a long time after Pangs.
His relationship with Harmony seems to be over for good.
He and Buffy have childish fights that'll soon turn into True Love in Something Blue.
Vampires Lore-wise, we learn that a vampire who doesn't get feed deperishes like a human being and becomes skeleton-like.

Harmony: She can read. And it seems that her literature of choice is, if not Bridget Jones' Diary, at least one of Bridget's favourite books.

Riley: He's from Iowa.
His relationship with Professor is mentioned, he seems to have deep admiration and respect for her. That explains his reaction to the following events in Season 4.

Giles: He's english. He says 'bloody', which is a common point he shares with Spike. We already knew that, though.