I know both, but the other person only knows one.
https://gyazo.com/e49c6aedd96a9f83c6a93694f6f6e68e
A series of pictures of two people saying different things
---
This page is auto-translated from /nishio/自分は両方知っているが相手は片方しか知らない. If you looks something interesting but the auto-translated English is not good enough to understand it, feel free to let me know at @nishio_en. I'm very happy to spread my thought to non-Japanese readers.