If the synopsis for Mint Chocolate's first volume is giving you flashbacks to the 1990s, there's a very good reason for that – not only is it adhering pretty strictly to the tropes made popular (or at least famous) by Wataru Yoshizumi's 1992-95 manga Marmalade Boy, it doesn't really do anything that's at all new. In fact, I was so firmly convinced that I had read this book before that I combed back through years of records of my reading (a requirement at my high school that stuck) to be certain. It turns out I had not, but if you've been reading shoujo manga since the 90s, there's a good chance that the same feeling may strike you, too.

Mami Orikasa's take on the stepsibling romance follows Nanami and Kyouhei, two high school second years. As appears to be the norm in the world of manga, the two are mostly unaware that their parents are dating and on the verge of marriage until things are at the point of no return. This holds more true for Nanami, whose mother waited until almost the literal last second to inform her, but Kyouhei hasn't known for much longer. Therefore she's completely unaware that her classmate, whom she's had a crush on for almost a year, is about to become her new stepbrother. To say that this is an awkward reveal may be understating things – Nanami is torn between genuinely wanting her mother to be happy and utter horror at what her mother's happiness entails for her.

She's certainly within her rights to be upset. Even if we ignore the trope where parents keep remarriages secret from their children, Nanami's being asked to change her feelings on a dime. That's not really feasible, and one of the major saving graces of this volume is that even she doesn't expect it to work out or be easy. That her mother doesn't know that she's been nursing a crush on her now-stepbrother does help with this, because really the only person censoring Nanami is Nanami herself. She's unwilling to let her parents know about her feelings because she wants them to be happy and not worry about something she views as entirely her own problem, and she also tries not to impose her issue on Kyouhei. It's not clear whether she assumes that Kyouhei also feels that their new status as family is weird, or at least awkward, and that really comes down to two things: how hard she's trying to get her own emotions under control and that Kyouhei is sending her really mixed messages.

While Nanami can be irritating at times in the book – she's one of those characters who is loud even though manga has no actual aural component – Kyouhei feels like more of a problem. In part this is due to the fact that he's a combination of shoujo romance's two least appealing (or least healthy, at any rate) romantic interest tropes: he's something of a jerk and he's much freer with his hands than with his emotions while summarily ignoring all of Nanami's protests. The implication that Orikasa appears to be going for is that Kyouhei has had a thing for Nanami all along as well, but started trying to come to terms with it a few months earlier, when his dad let him know about his impending elevation to brotherhood. Now that he finds himself living in close proximity with the girl he likes, however, his willpower is weakening and he just can't help himself from time to time. While this certainly leans into the toxic idea that men (and usually only men) have needs and can't control themselves, the more interesting piece of the story is that both Kyouhei and Nanami are actively trying not to like each other anymore. That Kyouhei's methods involve a certain amount of straight up ignoring Nanami, including when she says she doesn't like something, undermines that.

The chief issue with Mint Chocolate, though, isn't the stepsibling romance or the fact that Kyouhei can be a jerk and Nanami a twit. It's that there's almost nothing in this volume that we haven't seen before in numerous other stepsibling or similar moderately forbidden romances. Even the title calls to mind Marmalade Boy, with the idea of combining mint and chocolate intended to convey the “flavor” of their relationship in the same way that marmalade is meant to represent Yu in that other series – a combination of slightly bitter and sweet in a pretty package. While the art makes some interesting choices, such as the decision to give Nanami a more pear-shaped figure than we typically see in manga, which is a nice detail, it isn't enough to make this stand out as anything new or special. If you really love the trope, this is probably a bit more palatable, but even then it's hard to strongly recommend it because it really doesn't do anything new with the genre. If you've read Marmalade Boy, We Must Never Fall in Love!, Beware the Kamiki Brothers!, or even Domestic Girlfriend to a degree, you already know what's going on here.