27:50 (excuse me for opting for English, I don't know much Japanese, and I'd initially meant to comment this when I'd watched the video but forgot for over a week lol) In English, we call an action recently associated with that hand movement "mewing", mewing involves applying a certain tongue position to aid in gaining a strong jawline - it's been practiced for a few decades now. Younger people have applied extra steps to form a meme around mewing, such biting/sucking one's cheeks in and/or performing the hand motion seen. It started to spread through mainly TikTok, and has hints of a meaning of "humourously acting as if one is of high status / attractiveness / respect, while the doer generally doesn't actually think of themselves that way".
