I will preface this post by saying that it is possible that what I read was an exclusive publishing in my country, so it might be very difficult to find. I made my own research, and couldn't find the name of the series, despite how many details I knew. It seems to be extremely niche.

Anyway, it's a manga that I remember having quite a good story in my opinion, that was short, only 4 or 5 volumes. I remember a lot of details. It's a thriller so I'm about to spoil my memory of the story and what I remember of my interpretations. I know the main character looked bland classic black hair highschooler, the female lead was blonde. The story focused on people who were born on february 29th, and how for some reason their august months were scrambled (the days were switched), and the antagonist was a murderer that for some reason only ever killed people who were born on february 29th (I could be wrong about this, those are conclusions I made while reading). The main character basically has a very shaky month, alternating between the early days of the months, a warm hearted romance, and the later days of the month where a dramatic event happened and his life is miserable. Very rocky. Then, he discovers that the female lead gets killed, and he decides to manipulate his time scrambles to save her somehow. I also remember that there was a random bunny mascot suit theme somewhere in there for some reason. I think the manga released in the early 2010s, but nothing exact that I can pinpoint, maybe it was like 2016.

I hope someone can help, I'd love to reread it, I have strong memories about this series and I want to know if it's as good as I remember it. I did my research but really couldn't find anything.

Edit: title found, Title = drop frame. Thanks all.

it is possible that what I read was an exclusive publishing in my country

So it might not be manga (manga = originally published in Japan)? Can you tell us the country and/or the language it was printed in?

Don't expect proper grammar from me. I am not being paid here, so you get internal monologue in written form.

It was published in Canada. But it looked a lot like manga is what I mean. Published in french. I think it was translated from japanese but it's possible it wasn't. But since all the events of the manga happen in Japan, I'm almost certain it was written by someone Japanese, which also means it was probably originally published in Japan.

where did you read it? Library, borrowed from a friend, in book store etc

Don't expect proper grammar from me. I am not being paid here, so you get internal monologue in written form.

I borrowed it from a public library.

Your best chance is to look at the catalogue of that library or go in and ask a librarian at it. Where I am most graphic novel series are replaced when they wear out rather than removed from the catalogue. Even if they are no longer in circulation a long term employee (or whichever employee is in charge of curating their graphic novel section) will likely remember it.

Another possibility is if you are still a member of that library (many stay active for years even without use) they often have record of what you checked out in the past. (Mine has my checkout history going back more than 10 years so you might get lucky)

Don't expect proper grammar from me. I am not being paid here, so you get internal monologue in written form.

Thank you, I don't live near there anymore so it will take a while, but once I get the chance I will go and see if it's possible to find the title.

does the library have an online catalogue you can check? Also you might be able to call them even if you no longer live near by.

Don't expect proper grammar from me. I am not being paid here, so you get internal monologue in written form.

They do have an online catalogue, I already researched it, and I believe they removed the series from the database. Also I checked my borrowing history online, but it only saves it up to 5 years ago, at least online.

i think the manga you are looking for is Uranus (may be) which matches all the specific details you provided.

I don't know if you're serious, but I can't find any manga with that title.

Have you tried using http://nautiljon.com for finding what manga has an official french manga. (I can't vouch for how good it is since I don't know french but I did look and it seems to have a good filter so worth a shot. the website was recommended on reddit for finding official french releases)

Don't expect proper grammar from me. I am not being paid here, so you get internal monologue in written form.

Thank you. I found it with the search engine. Title = drop frame. The filter is what helped me lol. It has such a better filter than any other site. It was also never translated in english, only in french. So explains why I couldn't find it on EN databases. But yeah, big thanks, man. Very helpful.