Momoko Touyoko

Momoko is Yumis friend and a high school first year student. She has a lacking presence and is often ignored by her friends despite her efforts to gain attention as such she soon gave up on building relationships with other people. After a match through LAN mahjong Yumi acknowledges Momokos skills and finds her the two become friends afterwards. Her mahjong playing ability comes when she augments her negative presence into an advantageous stealth state causing her opponents to miss her moves. Source: Wikipedia