A Promise Between Lifetimes : Rewritten by fate

Ohm Pawat Chittsawangdee, a renowned antiquarian at The University, is cold , silent but also a genius at his field who has found many antique historical items. He looks cold on surface but he deeply care for his family and his boyfriend.
Nanon Korapat Kridpan is a history lecturer at the same university who may look easygoing and sweet but equally strict when it comes to studying. He and Ohm started of as friends and now is in relationship for 2 years.
Their sweet life get crossed with many interesting facts when ohm found an over century old diary with full of mystery he couldn't solve on his own so he seeks nanon for help to solve the mystery. They worked together,they found out so many entanglement with their current life and the diary.
A simple diary bought many drastic changes to their life. Past and present connected and amazing fact was that it even made sense to their current life. All the mystery unfolds little by little.
A actual promise between Lifetimes which was so sincere even fate has to give up infront of their love and rewrite their story. A story world refused, a story which was forced to buried but later fought to blossom again.