A Full Review
Penguin Gentlemen (Penguin Shinshi) by Ueno Kishi is a oneshot/one-volume manga about penguins depicted as tuxedo-wearing gentlemen working in a bar and restaurant and living amongst humans. This reminds me of Nyankees, but whereas Nyankees told a fictional story with the animals-depicted-as-people gimmick, Penguin Gentlemen doesn't. The "story" are disjointed vignettes covering all sorts of topics from what penguins eat to mating rituals to number of species to molting. Like it or not, you gonna learn today. The manga is a hardcover release with several color pages and the art is super nice.
If you like the penguins-as-people gimmick but want to skip the educational part or just want no context to any of it, just visit the mangaka's bomb-ass twitter (18+ as not all of it is safe-for-work). Or read this anyway and visit the twitter. I like and do both. XD Also, if you're looking for more art and artists to follow, Kishi retweets a lot of other people's works too so you'll have a nice full timeline of magnificent art.
I'm looking forward to more of Kishi's works!
Yen Press publishes the manga.
What to read/watch after reading Penguin Gentlemen:
I am a Cat Baristsa by Hiro Majima
Penguin & House by Akiho Ikeda
Penguin Highway, anime film and novel
Penguindrum, anime, light novels, and manga
Nyankees by Atsushi Okada
The Emperor and I by Mato
Tuxedo Gin by Tokihiko Matsuura