Its basically when a person is dating someone but still likes their old crush/ex.

As for background info, in the book Tiger's Destiny by Colleen Houck, the main female character has to admit that she still loves the older brother even though she's betrothed to the younger brother. She does this while walking on coals in a phoenix's realm deep in the ground while the phoenix was watching, asking difficult personal questions. She gave in to the phoenix when she proffessed her love for the older brother. Unfortunately, he thought she died, but she actually was restored to full health and taken to the phoenix's home on the mountain. That shouldn't happen to you when you give in to the phoenix though.
After the girlfriend had been hanging out with her ex all day and realised she still likes him. She proceeds to flirt-

Girlfriend -"hey, I wanted to let you know... I'm giving in to the phoenix."
Ex-boyfriend -"what does that mean? That's totally random."
girlfriend -"go read tiger's destiny."
by ForGreBidEnDen July 7, 2014
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