If you're looking for manga similar to The Girl Who Leapt Through Time: After, you might like these titles.
Never far from the future. In this world, all children are gathered up onto an island known as the Juvenile Circle. They receive their education there until the age of 18, when they graduate and go into society as adults. A boy named Shizu was overcome with strange feelings of anxiety the day after his graduation. Were they directed towards becoming an adult? Does he want to remain a child? It was neither of these. Anxiety embraced Shizu. The anxiety would lead him towards the truth of his world.
The only non-clone at St. Kleio Academy, a school dedicated to the clones of great historical personages. Shiro's father is a professor at the academy. Why is a regular kid taking classes at the school? Nobody seems to know for sure.
It's fairly obvious to Terui Chiaki that her classmate Ajikawa Yoshio has a crush on her. He is completely not boyfriend material in her eyes and, even if he was, Chiaki already has a boyfriend. Their mysterious teacher Mr. Yamada sees this relationship between the two students and offers an experiment. He is able to make copies of people and objects and does so with Chiaki, creating a copy of her, except the copy has no knowledge of her boyfriend. Yoshio will hit on the Chiaki copy, who is named Koaki, and he'll try to make her fall in love with him. After a specified amount of time, the copy and original will be combined back together and which ever love is stronger between the current boyfriend and Yoshio will overwrite all other emotions. So this love experiment begins and both Chiaki and Koaki, being the same person, thinks Yoshio has no chance in hell but with each passing day, some feelings begin to bubble.
All ordinary students must participate! Aliens, invisible men, skeleton dummies and the other extraordinary students must also participate!! Why? Because this year the committee head is Hanayashiki Miyako!! Even if it's pouring rain or a meteorite crashes down, the cultural festival will be a hit because the amazing committee head is there to keep it going!!
In Kyoto in the year 2027, Naomi Katagaki, a male high school student encounters a person who claiming to be Naomi from 10 years in the future. Together, they must change the future and save a classmate, Ruri, whom the younger Naomi starts to date in three months.
The mysterious game called “Heart of the Girl.” A game where in the real world, girls are rated by their ‘rarity’. Will Nozomi be able to clear her former bestfriend, Kakoi? Find out in this heart-racing story of love and skirt-chasing!