J. August Richards joins the regular cast and is billed in the opening credits as of this episode. This is also Andy Hallett's first appearance as The Host, later known as Lorne. Hallett is a regular guest star from this episode on, and eventually joins the regular cast during the fourth season.
One of the demons seen in Caritas belongs to the mouthless telepathic demon species previously seen in Earshot (1999), though this one wears a robe while the ones in "Earshot" were naked. Another demon, sitting alongside Mordar the Bentback, looks quite like the reptile-headed demon trapped in the Initiative in New Moon Rising (2000).
Edward James Gage, who plays Mordar the Bentback, also played one of the movers in Buffy vs. Dracula (2000), which aired immediately before this one when originally broadcast.
In the beginning of the episode, Lindsey remarks that "She likes Chopin and Brahms," while starting Prelude in C Minor in the CD player for Darla. It never goes further than this, but... Prelude in C min is used by Barry Manilow as an intro to "Could It Be Magic." His follow-up album the next year, Manilow II, included Mandy, which Angel sings for The Host, and later on admits that he thinks "it's pretty." The Manilow crush reveals Angel is at least a little aware of pop culture. But it could just be the old favorites being echoed in new songs that catches his fancy after wandering the earth for a couple hundred years.
This is one of the first episodes in which demons are shown of being capable of doing good. Angel experiences guilt after killing Jo's demon protector because he killed "an innocent being" and "a soldier like [him]self", and because it never occurred to him that a demon could be either of those things.