Recommendations

Although these two are really different as Anniversary Anyway focuses more on the pleasing side of the teenager's life and on the other hand The Guilty Secret gives importance to the sides of life of different teens-Happy, Painful, Beautiful, Memorable, Fun, and treasurable moments of life but shows most of betrayal and of secrets.
The thing that has in common is how sweet the development of relationships is in high school. In short, Romance is the thing that makes them similar- just sweet and delightful :)

big friend group in both
multiple couples
high school
multiple leads
love revolution is very lighthearted and fun

It's very similar it because it's also about school and it's was really fun to watch. Even the covers look alike

Investigations on a mysterious woman Toko started when Sonoe, a teacher and Toko's fellow faculty member, was found dead as a result of what seemed to be an unfortunate accident. Eiki, an insurance investigator, and Takeshi, an ambitious police detective, find links between this case and the deaths of Toko's 3 fiances, and are determined to uncover the truth.

No similarity in story, but same female lead and 2 very good looking male leads. It's similar in terms of having eye candy casts and males showing some abs:)

One is the drama, the other a deleted scene.
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Both are about a relationship between a celebrity and a non-celebrity who end up involved.
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Both are GL stories.
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Both are GL stories.
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Both are GL stories.
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Both are GL stories.
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Both are GL stories.
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Both are GL stories.
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Both are GL stories.
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Both are GL stories.
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