 If you liked
ReLIFE
|
 ...then you might like
Inuyashiki
|
Both involves characters whom were having a shitty life, until they got some sort of second chance opportunity that has change their lives completely, but they both have some difference where one voluntarily becomes a live tester for a fountain of youth drug while the other is an old man who has obtain by accident an array of weapons and tech that would make him Cyborg's grandpa.