 If you liked
Ore ga Doutei wo Sutetara Shinu Ken ni Tsuite
|
 ...then you might like
ReLIFE
|
In both series, the main protagonist gets the chance to make changes about his past life. This takes them to high school where they meet former classmates and acquaintances. As the story progresses, we learn more about the past life of the main protagonist and the experiences they've shared with others. ReLIFE is more known for its experimental approach with much more comedy and subtle romance. Ore ga Doutei wo Sutetara Shinu Ken ni Tsuite also has romance but contains more mature context with some sensible concepts.
>> The MCs go back to high school (whether it be via time or through... science), and must rediscover themselves truly to make it a worthwhile experience