A catchy and incredibly swaggerish to say lol it will make more sense once said aloud for yellow l looks very funny written down. However, aviod overuse for it can be easily seen as a "valley girl" thing to say

Internet persona(s) who happens to follow you and you happen to follow them back and maintain communication with and have a mutual liking for eachother whether it be friendship wise, etc. (Mutuals if more than one mutual)