This may be complex but not hard for me.
*concentrate chakra on his fat deposite turning some of them into calories and then into sheer expansion chakra*
Ok, now you may experiment sudden increase of gravity lili-chan.
*make a single handseal molding the chakra, and places the hand on lili's ass boobs shoulder releasing the chakra into her tiny body. Steadily she beings to grow further and further.*
This is going well...
*keep the baika charka flow steadily so that lili can grow back to her normal size. I "accidentally" let a a bit of chakra slip into lili's boobs makinng them a bit bigger but not affecting any of her taijutsu or ninja capabilities*
oops <-< >-> <-<