What a blast from the past! That pairing really takes me back to the early Creepypasta days. Honestly, the most fertile ground for that is still Archive of Our Own, but you gotta get creative with your search tags. Don't just search "Hoodie x Masky"—try using the 'Marble Hornets' fandom tag, or look for 'Tim Wright' and 'Brian Thomas' separately.
A lot of those stories get buried under the broader 'Creepypasta' tag, which is swamped with Jeff the Killer stuff. Sorting by relationship and then filtering for completed works helps. There's a specific author, goes by 'spectralsyzygy,' who wrote this incredible slow-burn series where their connection is built through shared, mundane survival tasks while on the run. It’ elects away from just horror and gets into the weird domesticity of hiding out.
Fanfiction.net is a graveyard for that specific niche now, but I did stumble on a few decent ones on Quotev years ago. No idea if they’re still up. The vibe of those stories is usually less about slash and more about two traumatized guys who maybe understand each other a little too well.