Natsuiro no Sunadokei - Recommendations

Alt title: Hourglass of Summer

If you're looking for manga similar to Natsuiro no Sunadokei, you might like these titles.

Steins;Gate: Enkan Rensa no Ouroboros (Light Novel)

Steins;Gate: Enkan Rensa no Ouroboros (Light Novel)

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Steins;Gate Movie: Load Region of Deja Vu

Steins;Gate Movie: Load Region of Deja Vu

Revolves around Kurisu Makise as she tries to save Okabe Rintarou from his uncontrolled leaps in time. Kurisu must decide if she will save him as his lover, or not bring him back to the main timeline with her morals as a scientist.

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Steins;Gate: Chouyoku no Divergence - Reverse (Light Novel)

Steins;Gate: Chouyoku no Divergence - Reverse (Light Novel)

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My Merry May Believe

My Merry May Believe

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Steins;Gate 0

Steins;Gate 0

November 2020, the Beta World Line… In this world, Rintaro Okabe has given up. After suffering through indescribable grief and untold heartbreak, he gives up on saving the girl he loves. But one day, he meets her again, just not as he knew her. From this chance encounter, the gears of fate would begin to turn once more. The heroes of Steins;Gate return for a new time-altering story set in an alternate world where the Future Gadget Lab members failed in their original mission. Can one final chance lead to a happy ending?

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Steins;Gate

Steins;Gate

The eccentric mad scientist Okabe, his childhood friend Mayuri, and the otaku hacker Daru have banded together to form the Future Gadget Research Laboratory, and spend their days in a ramshackle laboratory hanging out and occasionally attempting to invent incredible, yet generally useless, futuristic gadgets. However, their claymore is a hydrator and their hair dryer flips breakers, and the only invention that’s even remotely interesting is their Phone Microwave, which transforms bananas into oozing green gel. But when an experiment goes awry the gang discovers that the Phone Microwave can also send text messages to the past. And what's more, the words they send can affect the flow of time and have unforeseen, far-reaching consequences...

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Robotics;Notes: Dream Seeker

Robotics;Notes: Dream Seeker

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Robotics;Notes: Revival Legacy

Robotics;Notes: Revival Legacy

In 2019, childhood friends Yashio Kaito and Senomiya Akiho are together in their high school's robotics club, but it is in danger of being abolished. Akiho wants to preserve the club, as she feels like it is her last link to her older sister, a roboticist. Akiho has only Kaito to rely on, but he's more interested in the game "Kill Ballad Online." It turns out, though, that Kaito's obsession with Kill Ballad may come in handy for their robotics club, and there are other allies they'll meet along the way!

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Island

Island

Urashima, an island far from the mainland. The people who live there lead carefree lives. But five years ago, the island's three great families suffered a series of misfortunes, and succumbed to suspicion. The people of the island cut off all contact with the mainland, and began a slow decline. The key to saving the island lies in three girls who belong to the three families. But they are bound by old traditions, and are conflicted. On that island, a lone man washes ashore. The man claims to be from the future, and he begins a solitary struggle to change the island's fate.

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AOKANA: Four Rhythm Across the Blue

AOKANA: Four Rhythm Across the Blue

The invention of anti-gravity footwear has opened an innovative world of sports for students across the globe. Dreaming of flight since childhood, Asuka can’t resist the action-packed competitions of Flying Circus. But with her head in the clouds and a clumsy disposition, she’s got a lot to learn before she can go toe to toe with the toughest challengers at other schools.

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