Explanation: Scp-091 could appear in one of the secure storages.
When you eye contact with it, a message will appear saying "You feel nostalgic", and then you get deafen (but you can only hear your voice), making in the game more difficult to survive.
Then the player will say things like: "Remember when I tested with scp-173? Yeah, that tissue box was there" or "Remember when this breach started? Yeah, that tissue box was right there".
When you start a new game with scp-091 discovered in other game, Scp-091 will appear in the start of the game.
Scp-091 can be grabbed or dropped.
When you put it in scp-914 on rough or coarse, scp-091 will transform in a normal tissue.
And if you put it on fine or very fine, Scp-091 will transformorm in a special tissue box that have tissues that help you by enlarging the blink meter in presence of scp-173
If MTF have eye contact with scp-091, they will transform into passive npc's and start talking about their nostalgic past events.
It's document can be found on the archives.
You can get an achievement by survive more than an hour in game with scp-091 effects on you.
Any other notes: There is a tiny possibility that the player says: "Remember that markiplier video I watched? Yeah, that tissue box had a nice pink moustache" or "Remeber that pewdipie video I watched? Yeah, that tissue box said me that i had to subscribe pewds for original content"