With a title that rivals those of many light novels in length and a reincarnation plotline, it would be very easy to make assumptions about Hato Hachiya's We Swore to Meet in the Next Life and That's When Things Got Weird!. Several of them can be done away with almost immediately: this is an original manga not based on a light novel, it's only slightly isekai (there's nothing to indicate that in their past lives they weren't just in Europe somewhere), and it's a May-December romance, not an incest one – that title could, quite frankly, have gone either way really easily. The other important piece of information is that this manga in no way takes itself seriously.

It does, however, do precisely what the title advertises: something definitely went awry in the main characters' reincarnation plans. Once upon a time there was a princess who fell in love with one of her knights, but, due to their different social statuses, they couldn't be together. The two therefore vowed to be reborn together in order to get their chance to freely love each other, which sounds very sweet, but some heavenly wires got crossed, and when the two of them meet in their next life, Yuko is thirty-nine and Haru is seventeen. Oops.

So obviously now the erstwhile princess and knight face a totally different set of obstacles, the most major one being that Haru is currently underage. He has no problem with dating Yuko, but she's definitely having some second thoughts about where this is headed, not the least reason being that if anyone stands to get in trouble over their relationship, it's her. Haru is at least marginally aware of this and he's very attentive to her concerns over how they look in public; even if he doesn't care what the world thinks, a piece of him understands that Yuko would like to keep her job and perhaps not go to jail. But he's also just so darn happy to have found her that this age thing doesn't seem like a major problem to him, especially when compared to their predicament in the past. In fact, he's so happy that even the girl his age who has a crush on him finds herself rooting for Haru and Yuko, because if Yuko makes Haru that ebullient, then she's okay with losing him to a bafflingly older woman.

Whether or not the idea of a nearly forty-year-old dating a teenager makes you squirm is still likely to be a deciding factor as to whether you want to pick up this book, however. Hachiya does have a light touch with the social implications and tends to play Yuko's concerns more for laughs than anything else, but there is still some acknowledgement in the text that people don't really understand Yuko and Haru's relationship, even when they're just sitting at a café and talking, which is not in and of itself a romantic activity. There's a lot of judgement sent Yuko's way, and while the book really isn't interested in social commentary on a serious level, it is interesting to note what people say about her and how they view her. Since not even Haru's friends make censorious comments about them (although his childhood friend admits that she wanted to at first), we do get the distinct impression that it's because the woman is older than the man that this is happening more loudly – or that maybe Yuko thinks that's the case.

Ultimately the book works because while those touches are there, they don't take over the narrative. Part of Yuko is simply flustered that she finally found Haru after nearly forty years of looking and hoping, and she does comment a couple of times that in the past Sir Harold was ten years older than she was, so she's not totally against an age-gap romance. (She just…wasn't expecting so much of a gap.) And honestly there's just something so sweet about seeing how happy they are to have found each other again that it takes a lot of the sting out of the setup. Hachiya also does their best to make Haru more mature – and Yuko less so – so that there's a sense of the two of them meeting in the middle, while also playing their attitudes for laugh on occasion. For example, the question of who pays for their date runs into the dual walls of “but I'm the man” and “but I'm the adult,” both of which are particularly silly arguments given their situation. (They end up making a third, shared, wallet, which I kind of love.)

The story is told in very short chapters of three to five pages each, which also works for keeping the story on the light and fluffy side of things. The longest chapter in the book is a flashback to their past lives, and in some ways it's the best simply because it isn't constrained by the humor of the main story, although it does return to the present at the end in a very sweet way. The volume itself, however, is very short, with only about 130 pages total, which makes it one of the more expensive volumes in a price-to-pages sense. The art, however, is nice and doesn't cut corners despite the brevity and light nature of the story – it's a fully-realized volume, just a short one.

We Swore to Meet in the Next Life and That's When Things Got Weird! is, at the end of the day, a sweet, entertaining book, even for someone whose favorite flavor of romance is not May-December. It's also nice to see the genders reversed from the genre norm, but really the strength of this volume lies in the way that it manages to have a light touch with the more difficult elements of the story while still including them. It's definitely something a little different from most of what's available in English translation, and worth giving a chance.