What's on your mug?

It means On the phone, really commonly used by people

Guy in text: I am OTP with someone Girl in text: Oh okay.

By Darkdoom2334

One Trick Pony A person who plays one character (or is good at one character) no matter WHAT. Mainly used in FPS (First-Person Shooter) games like Overwatch.

"OMG there are so many Mercy OTPs"

By Anonymous010913

I always see my friends saying “this ship is my otp

OMG THIS SHIP IS MY OTP

By Catloger23

On the plane

I’m OTP!

By jboo1

Only To Play

Used in League of legends, otp can be used by people who play only one character : "Yasuo otp"; a player who only play yasuo.

By Lpcote