A collection of twitter published manga by Kawasaki Tadataka, they're described as "short, ecchi" comedy. Four volumes and counting, they're all available in the Japanese Amazon site for FREE as Kindle e-book.

　　Volume 1:

　　Marie to Natsu no Umi (マリエと夏の海 , Marie and the Summer Sea)Tonkagya-san de no Manner (とんかっ屋さんでのマナー , Etiquette at a Tonkatsu Restaurant)〇〇 nao Nee-san (〇〇なお姉さん , 〇〇 Big Sister)〇〇 na Present (〇〇なプレゼント , 〇〇 Present)Himitsu no Are (秘密のアレ , That's a Secret)Tatoerunara (例えるなら , For Example)Succubus Moriko-chan (1) (サキュバス モリ子ちゃん)Succubus Moriko-chan (2) (サキュバス モリ子ちゃん)Koushoujin Mashike Masaomi (交渉人 増毛正臣 , The Negotiator, Masaomi Mashike)Pierce no Okayama-san (1) (ピアスの岡山さん , Pierced Okayama-san)Pierce no Okayama-san (2) (ピアスの岡山さん , Pierced Okayama-san)Ichiko to Maya (イチコとマヤ , Ichiko and Maya)Toshishita no Otokonoko ni Are Shichau Hanashi (年下の男の子にアレしちゃう話 , Falling in Love with a Younger Boy)Otsupai Undermining Kouka (おつぱいアンダーマイニング効果 , The Boob Undermining Effect)Katei Kyoushi no JK ga Usugi (家庭教師のJKが薄着 , The High School Private Tutor is Dressed Lightly)Chuu-2 Danshi no Nichijou (中2男子の日常 , Daily Life of a Junior High School Second Year Student)Fumio to Masashi (フ三オとマサシ , Fumio and Masashi)Bouken Otomesan A-chan (冒険乙女三アちゃん , Adventure Maiden Mia-chan)Serizawa-san no Houkago (芹沢さんの放課後 , After School with Serizawa-san)Volume 2:

　　Battle Manga Couple Niari-Gachina Asa no Koukei (バトル漫画カップルにありがちな朝の光景 , Morning Routine of Couples in Action Manga)Enkaku no Are (遠隔のアレ , Remote That)Tensai Planner Kyouko (天才プランナー京子 , Genius Player Kyouko)Valentine Hunter Matsuzaki (バレンタインハンター松崎)Are no Namae (アレの名前 , The Name of That)Awanai Futari (あわないふたり)Itsudemo Dokodemo Hata-chan (いつでもどこでも八田ちゃん , Anytime and Anywhere, Hatta-chan)Do Seiso Moeri-chan (ド清楚もえりちゃん , Super Tidy Moeri-chan)Isekai Janakute Iikara Kouiu Kankyou ni Tensei Shitai dake no Manga (異世界じゃなくていいからこういう環境に転生したいだけの漫画 , It's Fine if it isn't an Isekai, I Just Want to be Reborn in an Environment Like This)Himetaru Omoi (秘めたる想い , Hidden Thoughts)Asa no Misaki-senpai (朝の美咲先輩 , Miki-senpai in the Morning)Okayama-san no Himitsu (岡山さんの秘密 , Okayama-san's Secret)Jiman no Kanojo (自慢の彼女 , The Girlfriend I'm Proud Of)Kanashibari no Jutsu (金縛りの術 , Kanashibari Technique)Aruhara Kara Hajimaru Are (アルハラから始まるアレ , That, Started After Drink Pushing)Himetaru Omoi (秘めたる想い , Hidden Love)Okaasan no Toutta Koukou (お母さんの通った高校 , The High School Mom Went To)Tada ni Bou Gu (多田に棒ぐ , An Oddering to Tada)Sakusha no Toaru Yoru no Nikki (作者のとある夜の日記 , The Creator's Journal Entry of a Certain Night)