Spike makes a reference to he and Angel having some form of sexual history; a similar reference is made in Last Gleaming. However this may refer to Spike and Angel's experiences in Just Rewards (2003).
Last appearance of Jenny Mollen's character Nina Ash. Had there been a season six, Oz would have returned to help her with her condition.
Angel has sex with Nina, proving that he can indeed have "positive" sex (not like his "perfect despair" moment with Darla, and not risk breaking the Ritual of Restoration.
The writing staff had originally hoped that Sarah Michelle Gellar would return as Buffy for this episode, but Gellar was busy shooting The Grudge (2004) at the time. Writer David Fury says, "We did think she [Gellar] might be in the second last episode, just like Angel appeared in the second last episode of Buffy's finale. We thought we'd do that but wound up not". Statements were also made to the effect that Buffy appearing in the episode would have taken the focus too much away from Angel.