The manga was shounen ai/yaoi. It was about a black haired guy that was on a mission or something on an island/facility and found a little boy there. The boy escaped with the older black haired guy and raised the boy. I think in the future the boy is grown up and starts having feelings for the black haired guy
I’m sorry thats all I remember 😔
If that rings a bell PLEASE let me know!
It wasn’t a long manga but I don’t think it was a one shot either

Gareki no Rakuen?

[img]https://i.imgur.com/6MBFpsv.png[/img]
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