MTL - Strong Waist - Chapter 10 defensive gate

She had a lifetime of fake virtue without receiving a virtuous ending. In the next lifetime, she controls fates with the flip of her hand. To the jerk who wasn’t faithful, she’ll draw a premature death talisman for him. For the poisonous step mother, she’ll send a death flower. For the step sister who is two faced, she’ll personally rip off that fake pretty face!

But when she personally offered up her body to her nemesis because of a child who she had no fate with, something unexpected happened. The night of the big wedding, the groom changed and a cold and luxurious man pushed her down. “You can marry whoever you like, but you can only give birth to my children!”

- Description from Novelupdates

One morning, after being bound to the system, MC started his routine of always being captured/ attacked by the ML.

She had a dream: the world was brimming with light. Family. School. Friends. Trains. Buses. Movies. Books. In that world of light, she grew into adulthood… and at the very end, in a white room, she fell into darkness. She awoke from the dream to find that she had become a demon. In the demon world, she lived a carefree life until she encountered a powerful being.

“Hey monster, you're not ready for this blow, but I don't give a shit!!” said Lian as he drew a circle inside another circle in his mind.Then, a few seconds later, a fireball as big as a house hit a monster just over 4 meters tall...It was a waste of resources, but it was damn fun!“BOOM!!!” he said as the fireball reached the monster, covering it entirely.The excitement on his face was palpable as his clothes and hair fluttered from the power generated by the impact.[Accuracy: 97%]“Tsk, it's really hard to achieve 100% accuracy when casting spells... that just means I have to do better!”Meanwhile, the monster and the entire area around him was destroyed. The crater was huge, flames burned the ground, and ash mixed with dust covered the air.---In a world full of Gates, Mages and Knights work together to defend humanity from extinctionLian, a boy from a small town, awakens a very... unique system.Casting spells by drawing strange shapes in his mind had become normal for him by now.Thanks to the system, he had become a Mage, a human capable of using mana to cast spells.Facing monsters from the Gates had become routine. Studying magic was a pastime. After all, he had the System, he didn't need to study classical magic. Or maybe not...