Perfect Propose

Both dramas portray the Tsundere vibe, stand offish but also shows affection to their lover. They also both have aspects of school and work.

To me, Perfect Propose is what Minato Shouji Coin Laundry should have been - a compact well laid out story about two people who recognize their need for each other. Both have similar plot lines where one-sided love that turns into something more and arguably deeper when the other realizes the deep connection they have. In both you have a chaser who is infatuated with the other because of the little things that meant something more; they are caring and attentive to that person’s needs and takes a while for the other to recognize and appreciate that - food plays an important aspect in this regard.

Hiro's so stressed out at work that he can barely have proper meals or get some well-earned sleep. When he passes out on the sidewalk after yet another stressful day, an unfamiliar face calls out to him - apparently, they once promised to marry each other? What's Kai Fukaya's deal, and why is he so insistent on assuming the role of Hiro's fiancé?

First of all, they have the same screen writer which explained why the flow of the story in the drama version was adapted in similar way.

Aside from that, both stories are started with two childhood friends who haven’t been with each other for a long time met again and sharing home.

Perfect Propose and Living with Him are different, but they are both providing cozy and comfortable love story about two people living under the same roof taking care of each other and figuring out their more than friends feeling.

Hiro's so stressed out at work that he can barely have proper meals or get some well-earned sleep. When he passes out on the sidewalk after yet another stressful day, an unfamiliar face calls out to him - apparently, they once promised to marry each other? What's Kai Fukaya's deal, and why is he so insistent on assuming the role of Hiro's fiancé?

In both series, one of the main characters is hardworking and has no personal life when someone from his past suddenly shows up and tries to make him happier and to get close to him at the same time, using not only his charm but also good cooking skills. Perfect Propose is just more mature.

Japanese romance with the same light vibe to the narrative, somehow. Both treat their characters with fariness and develop them in a similar way. Also, they're both the type of series that gives comfort to people who watch them, because the plot is fairly uncomplicated and more realistic in a matter of actions-feelings.
Kieta Hatsukoi is more juvenile, but it gives me the same vibe as Perfect Propose.