Though weak, these beasts are not unhappy. It's smiling, see! They're often in a dozy, distant sort of daze, as if they're unaware of the world around them, and tend to wander into places and things. They also like alcohol.
The Snapper is the Stage 3 Weak beast from the Terra family in Beast Signer. It is unobtainable in Beast Signer Alpha, since evolution is capped at the second stage.