Sgt. Frog Season 6 Episode 298 Mois: Farewell, Pekopon, Sir! / Saburo: Boy of Many Mysteries, Sir!

When Mois unleashes Armageddon upon Earth for real, Keroro is obliged to try and stop her, especially since he accidentally encouraged the Great Lord of Terror. Then, there are a lot of mysteries surrounding Saburo, and Fuyuki learns about one of them when he follows Saburo after school... and comes face to face with a number of parallel world Saburos!