Why does Saotome Genma always hold up an I Love You sign when ko'ed by Ranma?

Sorry about my sad lack of knowledge regarding Japanese culture, or something. Anyway, I noticed that Saotome Genma always holds up the sign that I read as "I Love You," in ASL whenever he gets knocked out by Ranma. I know it's not a Corna sign, because that one doesn't hold the thumb out to the side. I tried Googling it, but didn't come up with anything helpful. What is it? What does it mean?