10-nen Recollection

Towa, has had a one-sided crush for Shuhei for seven years. On the last day of junior high, on her way to confess her love, she suddenly collapses. When she wakes up in a hospital bed, 10 years have passed... She had slept without aging due to the hibernation treatment for her intractable disease... Surprised by the world 10 years later, she starts her high school life with high expectations. And then she is fatefully reunited with Shuhei, who is now a fully grown man, in a place she never expected.

(Source: Manga Mee, translated)