Related to shipping, OTP is an acronym that means “one true pairing”. As explained on the entry for shipping, fans will usually come up with fictional couples involving their favorite idols.

Among said couples (also referred to as ships), there is usually one that strikes people as the perfect one, in which both parties involved are perceived as made for each other.

Given the highly subjective aspect of shipping in general, a someone’s OTP might be someone else’s NOTP (the opposite of OTP, which consists of a play on how adding an N to the acronym would make it sound like “No”).