Class Developer of my Clones

Rumie was a game developer and an expert in the field of game making. He was assigned in making skills for each class of the game. Making him to have exhausted mind and body. Doing extra hours of overtime and sometimes went home late.
He was enjoying his work until his body gave up. He died of over fatigue and cardiac arrest. Making his passing an unprecedented one.
He reincarnated to the other world and lived a life without an awakening of his class. Then after many years, he faced the Demon God. Without a class, he was a weak enemy compared to him. All his friends died and also his lover. Making his life to be in turmoil. And in the last battle, he was defeated by his enemy and died. At last he was was about to rest. Until he was regressed to the past....... and this time was different.
Fate has other purpose and he awakened his powers and it was Cloning. To his surprise, they have class of their own! With that, his knowledge and skills as a game developer was put to use! He was also the one who manages the skills of his clones and made them from scratch. Making his second life not a boring one.