There's something exceedingly and painfully lonely about Kakashi in a tree, hidden among the shadows, lurking like the distant man he is. He could have team, friends, ...a life, if only he would let himself. But Kakashi never let himself have much of anything. He hid himself from basic social interactions.

Gai intended to break him of that habit. Even if it took years. So far, it had.

"My Rival!" Gai called up into the branches, shielding his eyes from the sun with his hand and grinning like a madman. Kakashi hadn't dashed away yet. Gai would consider this a good sign!
"I have not seen you in some time! Come down! I have lots of challenges planned for you!"