xoxi
An x-rated variation of the popular "xoxo" (hugs and kisses.)

xoxi stands for "Hugs and kisses and a boner."

Proper way to end (or start) a sexting session with your significant other. Based on the context, and who sends it, the meaning can vary slightly.
Guy texting his girlfriend:
Hugs and kisses and my dick says hello. xoxi

Girl texting her boyfriend:
I want to hug and kiss your dick. xoxi