Lord of End of World - Chapter 151

Some say reincarnation is a blessing, but for me, it's a dreadful curse. Cursed with endless reincarnation, I've been reborn as a villain 137 times. And all 137 times, I've been toyed with and killed by heroes who are far more cruel than the said villains... If I can't win no matter what I do, then I'll crush those so-called heroes at their very roots. - Quality Fan Translations, Made by Fans for the Fans - Villain Takes Over The Academy

This novel is also known as The Demons Beside Me

Chen Zhao can summon demons and see Death.

“Beelzebub, use your Gluttony ability to treat this patient’s anorexia.”

“Raymond, this old man wants to regain his manly function. You know what I mean.”

- Description from Novelupdates

A hundred years ago, Chen Qingyuan entered a forbidden zone called Sky Abyss, where his soul lamp extinguished, and everyone believed he had died. Today, although Chen Qingyuan has emerged alive from the forbidden zone, his cultivation has been completely crippled, and his spiritual roots are shattered. Faced with the remorse of lost love and the oppression of various sects, how should Chen Qingyuan proceed?“Chen Qingyuan, I'll give you two choices: one, marry me; two...”Inside Sky Abyss, there lives a girl in a red dress, with eyes like stars and a gentle voice.“I choose the second option.”Before the girl in the red dress could finish speaking, Chen Qingyuan decisively made his choice.(Main character with a dark belly + no system + humor + traditional fantasy + weak synopsis)

Fate, a gatekeeper who had been working for the castle, is beset by a few burdens.