At the end of the episode Reptile Boy, Cordelia has decided that “younger men are the way to go” by dating Jonathan. In the season three episode The Wish, Harmony bitchily suggests that Cordelia date Jonathan as he probably wouldn’t cheat on her.

In Bargaining (Part 2), Tara says of Willow, “Nobody messes with my girl”. This could be a reference to season two’s What’s My Line? (Part 2), in which Buffy says of Angel, “Spike is going down. You can attack me, you can send assassins after me, that’s fine. But nobody …

I’ve noticed that the middle window on the front door of the Summer’s house is painted black. Do we know why? has it always been that way? If not, when did it get that way?

In Enemies, just before we see Giles in conversation with the shrouded demon, there is a shot of the school from the outside where it is visibly night-time. However, in the very next scene the window to the right of Giles clearly shows that it is day-time.

In Consequences, Faith is strangling Xander and Angel has to get her off of him by hitting her on the head with a bat. As far as I can remember, Angel has never been in Faith’s apartment before. Did he manage to get in without an invitation? …

Nazis have been referenced a few times in Buffy:

In The Witch, Buffy says Amy’s mother is, “Nazi-like”.
In I Robot, You Jane, a student’s essay has been changed by Moloch the Corrupter, “This isn’t my report! Nazi Germany was a model of a well ordered society’? I didn’t write that! Who’s …

In many, many episodes of Buffy, the vampires do not get staked through their heart. i have seen them get staked further down and further up!

I am curious how many times Buffy had a hard time understanding expressions such as “hand over fist”, “right as rain”, etc. Can you provide a list of each occurence?

In the episode Anne, Ken asks, “What is Hell but the complete absence of hope?”. This may be a reference to the epic poem The Divine Comedy by Dante Alighieri where the gate to Hell has the statement, “Abandon all hope ye who enter here” engraved on it.