"Some people are worth melting for."
- Olaf, Frozen
Olaf is easily the most lovable character in Frozen (because he's just so naive and true in all that he does). And that makes him the best person to learn about true love from!
True love isn't just about feeling loved, but giving love, too! If you love someone, you must be willing to sacrifice for them, and expect nothing in return (seriously, he was willing to MELT. He would have DISAPPEARED! Sure, he might not have fully realized that, but still!) It's in that sacrifice that you can find the truest love of all :)