n tiny animal 

Perception +4; low-light vision, scent (imprecise) 60 feet

Skills Acrobatics +5 (+7 to Escape), Athletics +4, Stealth +5

Str +2 Dex +3 Con +2 Int -4 Wis +0 Cha +1

Lithe A weasel treats any tight space it can barely fit its head in or wider as difficult terrain and doesn't need to Squeeze to move through it.

AC  15; Fort +4, Ref +7, Will +2

HP 7

Speed 25 feet

Melee [>] jaws +7 (agile, finesse), Damage 1d4+2 piercing plus Grab

Constrict [>] 1d4 piercing, DC 15

Bestiary 3, page 291.