This is a good, simple story which you can watch as a stress reliever. I got intrigued by the title, but the meaning might lie a bit deeper into the story.

Jack o' Frost is a very cottagecore drama set around two working individuals, Ritsu and Fumiya.
Though they've managed to maintain a good relationship, strains soon appear and Fumiya suggests breaking up. Ritsu leaves enraged, only to get into an accident. Fumiya realizes that Ritsu has lost his memories after waking up. Not just any memory, but those that were specifically related to him. Fumiya takes this opportunity to erase his errors and give their relationship a second chance.

What I liked the most are the characters: they were not annoying, but understanding and was ready to give space to the ones they cared about. I doubted Fumiya's intentions because he seemed to be trying to help Ritsu, but trying "not" to fall in love with him again. But, during the last few episodes, I felt that his decision was the safest. Had ot been something else, things would look ugly.
But, the reason he broke up with Ritsu was plain stupid. It's literally he who is Jack Frost to me. Suzuki Kosuke did well, but his character was wtitten a bit too... pettily? But, I like his inner turmoil.

Ritsu's character (as well as the actor) was my favorite. I appreciated how he genuinely loved his work. He was confused, but still trying to give his all. Honda Kyoko knows how to act well with his eyes.
There were only two supporting characters, and this allowed the story to focus more on the main characters' alone, despite having only 6 episodes.

All in all, Japanese dramas have that quality which makes even the most plain dramas absolutely beautiful. This is not groundbreaking by any means, but give it a try if you feel like it.