Unused 7?

[Slexin]

This just appeared in my friend's inventory on PSOBB. Also why is the name of the server I use a bad word .-. I thought mentioning it would help idk.
I tried googling it but the only page that I could find that may tell me what it is crashes my browser when I open it.

[Kroniedon]

It's a dummy item. Means either your friend obtained an item that used to exist and was removed from whichever server(though I have a good idea which) it was, a glitch occurred inside your friends inventory and a dummy item was created inside it, or your friend tried to create an item via hacking and successfully created a useless unusable item. In either case, it should be harmless enough, but I'd suggest looking to the forums of the server in question as to whether or not it will be in use or should be in use in the future. If not, I would suggest selling it at a shop to delete it.

Condensed:
It's pretty much the same thing as the Missingno glitch in the original pokemon games. Only 151 pokemon yet 255 slots of data, 104 of which are filled with dummy data. Your friend has a dummy data item.

[Slexin]

Ahh, okay. That's boring, I thought he picked up/recieved something fun, haha. Thank you very much c:

[NegaTsukasa]

It has a data drain ability. Use it wisely. ;-D