Physically, Peep resembles a humanoid with stubby arms and legs. He also generally tends to give a signal whenever he's about to attack. The signs are:
- Smiles and brings his hands to his face: a spray attack that sends 10 urine projectiles in a radial burst.
- Smilling and throwing his arms wide: jumps to the position where the player was last.
- Frown and makes a burping sound: makes some gooze come out that damages the player if it hits them.
Duke of Flies | Gemini | Monstro | Larry Jr. | Famine | Steven | Widow | Pin | Blighted Ovum | Gurdy Jr. | Fistula | Gurdy | Peep | Chub | Pestilence) | C.H.A.D. | The Carrion Queen | The Husk | The Hollow | The Wretched | Monstro II | Loki | Gish | Mom | Mask of Infamy | Daddy Long Legs | Triachnid | The Bloat | War | Scolex | Blastocyst | Conquest | Teratoma | Lokii | Satan | The Fallen | Headless Horseman | Krampus |