Go Back to Sleep
Persocons don't sleep, everyone knows that, well everyone except Hideki Motosuwa of course. So every night as he leaned over and shut off the light and bid his Chii goodnight, he was completely unaware that she would lay there wide eyed, the whole night. She could always go talk to Plum and Kotoko but they were busy playing cards or sometimes-even scrabble in the corner. Needless to say Plum usually won all the card games, and Kotoko all the rounds of Scrabble and Chii didn't really feel like interfering with their "bonding".
So she would snuggle closer to her Hideki or play with his hair and sometimes-even trace little patterns on his chest with her small finger. Usually he would chuckle and mutter to Chii that that tickles and to just go back to sleep. Chii always giggled at this, because everyone knows Persocons don't sleep, well almost everyone.