MTL - Take It Easy - Chapter 187 extra

In an era when the power of Fire Magic was considered to have reached its limit, one girl began researching nuclear fusion.

Time travelling from the majestic era after the Recuperation of Reiki, he became Kimura Kazuki, a 16-year-old high school student in Japan, one year before the Reiki Recuperation.

Tentatively, he set out to hone himself to the bone, burning candles at both ends to stockpile resources in preparation for the imminent Recuperation of Reiki. His goal was to be many steps ahead of all humanity when the time comes.

However, it seemed like fate had decided to play a cruel trick on him.

One year later, the Recuperation of Reiki… did not happen as expected.

- Description from Novelupdates

Pinning her tall body against the hard wall, he looked into her beautiful emerald green eyes as he spoke in a deep voice, "I have two options for you," his body came closer to hers as he continued, "Be my girlfriend. Or," his lips turned into a sly smile as he whispered close to her ear, "Be my boyfriend." He even dared to wink right before her as his dark orbs glinted amusingly.