Ooh, this is a fun episode! We get to see more of Giles' backstory.
When we was an angsty and rebellious teen he did the stupid thing and rebelled against his watcher destiny. Then he did the REALLY stupid thing and started practicing demon...ology? Hmm, demonology is the study of demons...yeah, I guess that is correct.
Gathers his own little cult, they all tattoo themselves with this symbol and have wild and crazy fun summoning a demon.
Well, so many years later its come time to pay the piper. The demon is back and hunting down the cultist members. Ethan (the old colleague Giles beat to crap in the Hallowe'en episode) is back and has a plan to save his sorry hide.
The tattoo acts like a homing beacon for the demon, so Ethan tattoos Buffy and uses acid to burn his own off. clever clever.
Now, as a rule I tend to avoid demons as demons are just frickin' NASTY. However...summoning, possession, symbols signifying the mark of a demon (in this case the fictional mark of eyghon)...all of these are fairly common. Well, common at least when dealing with demons..and sometimes spirits in general.
The symbol supposedly allows its bearers to have a psychic link to Eyghon. Also entirely plausible. Aside from the nasty face makeup and glowy eyes, this episode is surprisingly...realistic, in terms of possession and whatnot. Even the jumping from body to body. Now its not as simple as in the episode--generally the said demon has to weaken their host before they can take up full possession, simple unconciousness isn't quite enough to do it. Oh, and demons can't re-animate corpses.
However, they way the solve the problem of saving the possessed Ms. Callender was really quite clever. Angel starts strangling her, the demon jumps to the nearest dead body--that is, Angel. Angel is cursed with a soul so a demon cannot inhabit his body--it destroys the demon. Brilliant truly.
Well, I could actually hold on the topic for quite a bit more, but unfortunately my hour lunch is up. Talk to y'all tomorrow!