Suzuki Jin is what got me through this. He is a good actor and charasmatic enough to keep me watching and to make me want a good ending for his character even if the screenplay is written simplistically.

While the screenplay does bring up various concerns one might have with an age gap romance, and social and familial navigation, it doesn't explore them well or deeply. It's not very insightful or thoughtful. A couple things come up repeatedly though they feel only partially discussed (like they're being used as a writing crutch), while others are resolved with unrealistic ease. There's way too much going on with the plot and side people so there's no time to explore things with more meaning. Character psychology and development stays simplistic as a result.

The set up is insanely fast. There wasn't adequate time for me to get invested in the characters before they started doing things that strained their likability. The first Ep of 20 min has Mayuki confess to Shino and them starting a relationship of sorts and growing some feelings, then it's all angsty struggles from then on. Shino's character was bland and I couldn't get invested in her.

There is a good amount of sweetness, skinship, and hugs, and a couple of kisses. The hottest scene is in the first episode (shows a bit of the lead up to the two main characters sleeping together).

Some suspension of disbelief is required for various things throughout the story.
General Spoiler below.
(Ex: who would start living with the person they are in love with and *immediately* leave their home in that state of disarray every day? Especially when it's a usually thoughtful character who is still trying to secure the other person's affection! That really came across as a forced plot point because the writer needed it to happen early on to prompt the "kid" arguments.)