OTP = One True Pairing

Refers to an author's preferred relationship pairing between certain characters within a fandom. (An OT3, for example, refers to one's preferred trio of lovers, when two just isn't enough.) Fans may have many pairings they support, even multiple OTPs in a single fandom for different sets of characters.

Gerita, Spamano, UsUk, PruCan and Giripan are all examples of the many, many, OTPs Angel has.