Azazel

Many smiles are good sign. This is a Slaanesh Smile. Slaanesh Smiles are NEVER a good sign.

A forgotten character from Warhammer Fantasy, Azazel was a Daemon Prince from the Gerreon tribe of the Old World (which would eventually come to follow Sigmar and form The Empire). He was rooted out for his Chaos worship by the God Emperorling himself and fled to the Chaos Wastes where he immediately pledged himself to Slaanesh. Azazel commands Slaanesh's forces, and is his general in times of war.

He was granted the same "look upon him and lose your will forever as the brain-blood forever exists within your genitals" power of Slaanesh. Literally no being (other than Slaanesh and maybe Sigmar) is immune to his appearance, which is both the most beautiful thing you will ever see and at the same time is the most horrifying. His shtick is to get you to look at him, where you (be you mortal or Daemon) get on your knees and beg for a taste of his cock. No, really. A Questing Knight sought to kill Azazel to prove himself to the Lady... only to fall to his knees and pledge undying devotion to Azazel when he actually encountered the demon (who promptly chopped his head off, with the knight offering no resistance, and probably skullfucked it too). Also a group of Ulric-worshipping knights swore before Ulric's flame to kill the demon or die trying, only to become the demon's subs complete with pet play and leashes (this not an exaggeration, this is legitimately canon).

His physical traits include:

• Hair blacker than anything in the Warp and finer than anything made by the hands of the Elves.
• Horns more magnificent than any mortal-grown ivory that crown his face like a portrait.
• Eyes that project innocence no being has ever known while also being as cruel as those of a shark.
• Perfectly white and delicate skin, to the point of almost non-existence.
• Perfectly proportioned limbs and features (one of which may be a horsecock).
• Wings whiter than his skin (somehow).
• Clothes made of silk finer than-aw, fuck it. It's better than you have, leave it at that.
• Bling, the kind so expensive they don't exist in real life.
• A magic sword that shifts form to match his graceful movements and yadda yadda, it's a fucking Hand Weapon.

Like Amon 'Chakai, he was just the same as his master and thus was completely pointless in the fluff and likely dropped to give Slaanesh more screentime. He was shown as a mortal character named Gerreon in the Sigmar Heldenhammer novel trilogy who betrayed Sigmar to serve Slaanesh, also killing his own sister (who was betrothed to Sigmar at the time). Also, he did get to appear and talk smack with his old enemy Sigmar in the novel for The End Times: Archaon, but he was promptly killed.