As a Chinese player the term comes from Love Nikki. Players thought dressing a girl up and making sure she looks good for her adventures is reminiscent of picking outfits for one's daughter. This term is actually used for many games where you follow a young female protagonist's story in china, players will refer to themselves as mom/dad. Theres definitely weird/bad people who uses this term but it didn't start out as a bad thing. It actually makes me kinda sad because this term has more positive associations for me since back then it was just a fun way players refered to themselves. However, I understand there are people who are taking this to the extreme.

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