Hae-In Joo

A student at Myeong-Ji's and Yeong-Ho's school. Hae-In is the wealthy heir to NV Group, with her mother being the current CEO.

Hae-In is a wielder of time powers with the ability to rewind time. In an attempt to become the master of time, she individually kills every student at her school one-by-one and rewinds time afterwards in order to single out anyone with time powers.

[Hae-In's time-based powers are later revealed to not be Rewind but rather Loop, with the real Rewind—[Neung-Dae Gwon)(https://anilist.co/character/346732/NeungDae-Gwon)—killing her and stealing her powers.]