Hello. It's BL story with world hopping. (quick transmigrations) The MC is system administrator. He isn't on retirement but he has holidays and he did a lot of work so he brings system and goes out. I can remember a lot but it has low connection... The first arc. He is a zombie. A king of zombie. He was ready to kill ML but he is somehow smelling quite appetite. There's labs which want the ML. And the MC helps him to smell their products. Before becoming system administrator he lives in cultivation world. The last arc was mix between his 'real' cultivation world (and his real life) and 'real' modern world of ML. I will be glad for any help!