Verb: To sit on another's face. Preferably a large, beautiful, ethnic ass, smothering a tiny unsuspecting face. "If you don't stop teasing her about her weight, I'm going to soyf you!" OR to fuck something up. "Well you really soyfed things up this time didnt you!?" OR having a leisurely day. "I'm just planning on soyfing the day away."
Noun: Can be used in a positive or negative connotation. "Hey wasn't that orange julius super soyfey?" OR "That dude is such a fucking soyf!