"Leftover women" (剩女; shèngnǚ in Chinese). A Chinese classification of women who are older than 25 and aunmarried. It's a term sponsored by the state and has appeared in numerous advertisements, tv shows and magazines to shame women in being single and "leftover".
Being ambitious, having more goals than finding a husband and starting a family (no offence if you DO want to do this) and being young (!!), happy and single is something to be proud of rather than to be shamed into.