After giving Tsukimi a make-over, Kuranosuke begins quietly musing as he and Tsukimi usually do when alone, telling his mother that he wants to put his skills to work showing all women that they're beautiful. The way he says it is just so sweet and wonderful and true, you can't help but smile at it.
Kuranosuke: Looks like it's go time, Mom. I'm gonna put my skills to the test. Deep down, all women want to be pretty, even those freaky spinsters over at "Chez Otaku." Every girl is born a princess, some of them just forget is all.
Kuranosuke helping Tsukimi and her friends raise enough money to buy their apartment complex. True, it turns out to be a waste later, but the fact that he went out of his way to help them is still very heartwarming.
Kuranosuke carrying Tsukimi to her room. Considering that this is after her Heroic BSOD and trying to drink her problems away, this was such a kind gesture from him.
The whole arc with Shuu trying to buy an engagement ring for Tsukimi.