Child of Light - Volume 11: Chapter 13 - Casting Another Forbidden Spell

Eren Idril died as an old, decrepit, and piss-poor adventurer by the maws of a D-Rank monster. He had a lot of unfulfilled dreams and desires that couldn't see the light of the day after the light in his own eyes died down.

But fortunately for him and unfortunately for the world, that wasn't his end. Eren was somehow dived back in time when he was a mere teen, attending Lionheart Academy for adventurers.

When life gives him a second chance, Eren decides to exploit it to its fullest. Experience his vile deeds as he partakes in them without feeling the slightest bit of hesitation.

Waking up, Kim Hajin finds himself in a familiar world but an unfamiliar body.

Mark hatched out of an egg one day, reincarnated as a demon!His body was as strong as iron, instincts capable of noticing a silent fly multiple meters away. Eyesight sharp enough to see the small holes in an enemy’s clothing.Moreover, he also had a system.[Soul Devourer][Eat souls to grow stronger.][Mind-type Demonic Tricks have been derived out of your demonic bloodline!][Heart Input!][Input unsolicited thoughts in an enemy's heart and influence them!]Mark took a deep breath.How can he allow himself to live a mediocre life after being given this second chance?Now, he wanted it all!Women, wealth, power, status, and even eternal life!His ambition was set, his heart was on fire. A demon had been born.

When a person dies, they either die light as a feather (aka unimportant) or heavy as Mt. Tai (aka very important).