I'm already having the impression that if "Dissidia Final Fantasy 2" becomes reality - with, as expected, more characters - Lenna (voiced by Nakahara Mai, of course) would be slated to appear alongside Bartz.

Isnt that the mouse/rat of yugioh that when destroyed let u search for a earth type monster?

No, this is a particularly dangerous (when you first come across them) random monster you can fight in Final Fantasy V called Skull Eater. Given her dialogue, Lenna has mistaken it for a Nut Eater, a palette swap of the same monster which is very weak.

Sucks that Lenna won't be in D2.

:(

That reminds me, there's another connection here besides Hoshi Souichirou.

Ryukishi07 (Higurashi no Naku Koro ni's author) commented at one point that Ryuuguu Rena's character design is based on Lenna's SNES sprite. There is also the whole Lenna/Rena/Reina namesake thing.