Do you know it?
Who is Yui?

She's a fictional character from some anime that a member has an obsession with. It has nothing to do with chess.

Yui Whoi?
Do you like
Green eggs and ham?
I do not like them,
Sam-I-am.
I do not like
Green eggs and ham.

Yui is my wife! She's the sweetest girl you ever could find! She plays the guitar and does cute things with her friends. Also she is cute, of course!
Yui is love and as such permeates all other areas of fun and loving. Those who have Yui's presence should consider themselves fortunate. THAT'S RIGHT, CHESS.COM GUYS! I could go on forever, but I'll stop here and I'll answer any other questions you have as you wish!
Threadly reminder that Yui is love.

It is more for kids that Yui thing I suppose.
Yes Yui is great with kids! Here she is with our daughter! Aren't they adorable?
And does it have anything to do with chess?