it's a oneshot (probably) in a 1-vol collection of oneshots.
it's about a girl who is about to graduate from high school and the boy who is in charge of making the video.
the girl and boy fall in love, but at the end the boy dies, leaving a video of her behind for her to watch.

thanks 🙂

Sounds like the oneshot 'Last Scene' in the 1-vol Honey Moon.