Some time before the June of summer. One day, she suddenly died...

"I" and the corpse of the girl who should have died, "Makoto", spent those false summer days in that apartment.

The relationship between these two sad, distorted people slowly becomes clearer...

Original webtoon (Korean webcomic)

The office of the Time Eliminator offers a unique service, the ability to eliminate an event that happened in the past. Rex, the man with the power to travel through time, may look young, but he's a professional. He goes back in time well-prepared, with various gadgets and even an earpiece for communication with his support in the present. While Rex typically takes on cases for profit, he's also particularly looking for ones that might give him a chance to obtain a magical "Babylon Item". The first case of the series is from the last remaining descendant of Fred Abberline, who was one of the detectives who failed to solve the notorious Jack the Ripper murders. Ever since then, the Abberline family has been cursed. Could the curse be the sign of someone in the past using a Babylon Item?! It's up to Rex to go back in time to the Jack the Ripper incidents and find a way to remove the curse from the Abberline family!

In the Koi Nanka Shitakunai series:

V.1 - Kyou kara Kyoudai ni Nari
When Nakajima's mother decided to remarry he was afraid but everything turned out to be even better than he expected. His new older brother helps him and spoils him a lot and they're getting along very well until the moment when Nakajima comes home earlier and sees his big bro playing with another guy in the bedroom. What's gonna happen from now on?

V.2 - Kyou kara Koibito ni Narimashita

How do you stop an assassin who takes pleasure in killing? Read about the story of Miyamoto Musashi's Last Successor.

From Anime News Network:
The story begins in the distant future in the far reaches of the galaxy. The Human Galactic Alliance has been constantly fighting for its survival against a grotesque race of beings called "Hidiaazu." During an intense battle, the young lieutenant Ledo and his humanoid mobile weapon Chamber are swallowed up into a distortion of time and space.
Waking from his artificially induced hibernation, Ledo realizes that he has arrived on Earth, the planet on the lost frontier. On this planet that was completely flooded by the seas, people live in fleets of giant ships, salvaging relics from the seas' depths in order to survive. Ledo arrives on one of the fleets called Gargantia. With no knowledge of the planet's history or culture, he is forced to live alongside Amy, a 15-year-old girl who serves as a messenger aboard the Gargantia fleet. To Ledo, who has lived a life where he knows nothing but fighting, these days of peace continue to surprise him.

From Twisted Hel Scans:
After losing his memories in a traffic accident three years ago, Haru is now living with Kiriyuu, his saviour and legal guardian. But after a school trip where he and his friends wander in an ancient lab, Haru discovers that there might be more to his lost memories than he thought.

The story revolves around a high school student named Shinya Matsumoto and his love story, which takes place in the summer vacation. Shinya unexpectedly encounters a car accident, which results in a mother and son being taken to a hospital. The son, Daisuke Kirishima, is completely fine while his mother, Reiko Kirishima must stay in the hospital for three weeks and is unable to look after her son thereafter.

A freshman in college, Amano, is taken a liking by a mysterious senpai, Kamishiro, who raises chicks. When Kamishiro hugs him out of nowhere in their first meeting, he thinks this senpai is crazy, but as he spends more time with him he sees how kind he is. But one day, while Amano is playing with the chicks, Kamishiro kisses him out of nowhere! An airheaded research student and a kuudere freshman's love story.

A tale of a dragon rider.

Hokuto Kuzuhara is a delinquent known throughout Sekai Private Academy. His way of life being so hated by his family that they give him an ultimatum: find a girlfriend within a year or move out. That said, though, months pass and he still has had no luck and it seems like he never will. It is then during this predicament that he is approached by the student council vice president with a plan that would both save him from moving out... As well as help her with her revenge.

Hito Natsu no Kids Game (ひと夏のKIDSゲーム Hito Natsu no KIDS Gēmu) is a short, debut manga work by Ken Akamatsu, the creator of Love Hina. The manga was published on September issue of Kodansha’s Magazine Fresh on September 10, 1993. Ken Akamatsu later received Kodansha’s "Freshman Manga Award" (Japanese: 新人漫画賞/少年マガジン新人賞) and Special Jury Award (Japanese: 審査員特別賞) for this work.The manga was re-published on 20 May 2001.

(Description taken from Wikipedia)

From Kodansha:

After a battle with an evil demon, an entire village is laid waste. All perish, except for one boy. Keeping his master's teachings close to his heart, this lone survivor sets out on a journey westwards in search of new sights and unimaginable power. The boy's name: Gray Fullbuster. For the first time, experience Gray's childhood adventures, and follow him down the path that will lead him to Fairy Tail!

Details the meeting of the founders of Fairy Tail and exactly what happened between them to lead them to found the guild. Told primarily from Mavis' perspective.

Someone is trying to kill Maejima, the unassuming Archery club adviser and Math teacher at Seika Women's High School. What appears to be pure, dumb luck has gotten him through several attempts unscathed, but he has no clue as to the perpetrator and the Principal would rather not involve the police in what's "surely just a student acting out". With the entire faculty and student body as his suspects, Maejima struggles to discover the culprit before his luck runs out.

Maya is a mysterious young girl who is hired as an assistant to detective Matsunomiya. The Imperial City of the Taisho Era has a mixture of Eastern and Western cultures... What kind of adventure will the two encounter here?

Mamoru is a Nishiarai game player who has switched to a first-class powerful new high school named Hijiri Gakuen Koukou. There he met with a group of eccentric game lovers who call themselves Dennou Kenkyubu, he accidentally joined and had to undergo a variety of events and adventures with them.

This is the story of several people that possess ESP powers, known as (PSI)

Biohazard 3: Last Escape is a series of Hong Kong manhua (Chinese-language comics) written as a tie-in to Resident Evil 3: Nemesis. It was published by SkyWalker Comics.

Story of Hatta Shuuji's encounter with problem-child and popular model Haru. Incidentally Shuuji is the childhood friend and ex-housekeeper of Maruyama Mie.