Yoongi was always able to control his regression. He had mastered the art of hiding and concealing it, pushing it away at unwanted times and keeping the secret. But what if it just gets too much one day and he regresses during practice? He slips right at the end and runs to hide, to force himself to be a big boy again. But Jungkook finds him and is very confused and shocked when he sees yoongi and even more so when yoongi calls him Hyung.