Chanko Bakunishiki

Takeko Superdeluxe (タケコ・スーパーデラックス) or Chanko Bakunishiki in anime is the minor character and antagonist of the food festival arc.

Takeko Superdeluxe/Chanko Bakunishiki is shown as a woman (man in anime) of enormous dimensions, wearing a coat that covers him/her completely, he/she has a menacing look, and his/her hair looks like a bamboo shoot (chonmage hairstyle in anime). But it's all a hoax, having a slimmer body, being all a paper mache disguise, where he/she hides a tank to store food. Rentarou describes him/her like some giant character in One Piece Universe.

(Source: 100Kanojo Wiki)