A Demon's Journey - Chapter 507 Earth Phasing Technique

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.

[Have you become more learned today?][Accounting for the capacity of your brain, your study efficiency has been increased to 28 times that of normal.][The remaining amount of energy you have for studying today, 26 hours.][You will enter an exhausted state when your energy is depleted and be unable to obtain new information.][Please relax by using the functions within the system and restore your energy as soon as possible.]With limited energy and the onset of fatigue, the Study Monster had no time to think too much--papers to come!Had the heavens not grant me this system, the unending sea of knowledge would seem like a long night.

The amiable looking patriarch is gazing at a stone monkey: “Wukong, what do you want to learn from me?” “It’s all up to master’s instruction.” The stone monkey respectfully replied: “As long as I will be able to beat up Tathagata, then it’s alright.” One hundred years later, the stone monkey defeated Tathagata and ascended the throne, becoming the Jade Emperor.

- Description from rhadoko

Failing in his job hunting, Sanada Kyouichirou was hopeless in this society. When kyouichirou had thrown himself towards the bottom of a cliff. When he woke up his body had returned towards when he was in fifth grade of elementary school. He did not want to have any regrets in this life so he had decided on building up an harem in this second life.

The elder sister that he admired, a senior and president of the student council at a school for rich young girls, a strong minded upper classman at school. The poison fang of Kyouichirou who had pretended to be a innocent child attacks those girls.