Flash Animation Anime
Koroshiya-san: The Hired Gun

The story follows the title character, who is regarded by himself and others as the best hit man in Japan. He goes by the motto, "If I have an assignment, I will kill anything." However, his "killing" assignments have expanded to include everything from summer vacation homework to housekeeping. "The hit man never fails to kill the target. Though he does not aim to, he also never misses the laughter."
[Source: Anime News Network; modified]
Kantoku Fuyuki Todoki

Insufficient Direction is the first essay manga by the "queen of the manga world," Moyoco Anno. The comedic and heartwarming autobiographical story followed her everyday married "otaku lifestyle" with Hideaki Anno (Evangelion), "the founder of the otaku cult."
[Source: Anime News Network]
Mazinger ZIP!

This is a series of animated flash-shorts produced on NTV's ZIP! television programs starting on April 8, 2013. It is set to replace ZIP!'s previous anime shorts Ohayo Ninja Tai-Gatchaman shorts based on Science Ninja Team Gatchaman.
Mazinger ZIP! features the same characters from the original series involved in a series of small comedic sketches.
[Source: MyAnimeList]
Choubakuretsu Ijigen Menko Battle: Gigant Shooter Tsukasa

The anime follows Tsukasa, whose dream is to become the best at Gigant Shooter (battles in a game similar to pog) in the world. The menko card his father left for him called King Menger is his partner. Tsukasa's fellow gamers are the cute but tsundere Koide Miruko, the spectacled bully Numata Manabu, and the realist and sharp-tongued Doumoto Ataru.
[Source: MyAnimeList]