Honestly how I came up with Likuu, was I was a noob back on FH with a really lame username, I wanted a fresh, clean name that nobody had ever really seen, one that's different from most.
I literally scrambled a bunch of letters together here and there, came up with a few and decided Likuu sounded the best. It just works for me, I use it for almost everything now.
People always seem to pronounce it differently, but when I first had it, I never even thought of how to pronounce it, until a friend of mine Owlus pulled me into a call and it was the first time we ever spoke, she pronounced it "Lee-coo" and now it just stuck.