My Classmate is 200 Million Years Old - Chapter 123

The last thing Ariel expected after a weekend of binge reading was to be transmigrated into the same novel as the evil secretary who was bound to be eliminated.“It's okay, I can just disappear from the main story line and live a peaceful life.”However her hopes were shattered when a system barged into her mind and pushed her to fulfil the dead secretary wishes. The top one, capture the male lead.As she saw the formidable man sitting in his office chair with leisure, the full time student Ariel who never had an experience wirh boys thought with dismay.'This is going to be a difficult task.'However, it was this or deathSo she plunged into the journey of seducing the male lead, unaware that once she gained his attention no one would be able to save her from his clutches......Transmigration. System. Multiple Love Interests with a focus on the alpha lead. Possessive, alpha Male Lead and lots of face slapping. Fast-paced.

Throughout this current life of mine, I will pay no attention to my past lives, nor will I seek future lives. I wish to live vigorously, to pay back debt of gratitude and fulfill duty to avenge, to defeat valiant heroes from all species, and to proudly laugh at all the Gods and Demons of the Six Path of Reincarnation!

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

After crossing over to Naruto World, Shiranui Yuuji found that there was an incomparably terrifying Godzilla in his body.

“You are Tailless Bijuu? Your chakra is astonishing…. What a coincidence, so am I.”

“You know Bijuu’s coat? I don’t have Bijuu’s coat, but I do have Godzilla Coat-”

“Bijuudama is terrifying!! It can destroy a mountain as soon as he sends it down?”

Hiss, that Bijuudama scared Yuuji, he quickly moved his hands to form seals,

“Nuclear Release – Atomic Breath!”

When Yuuji turned into Red lotus form, Godzilla pressed Nine-Tailed to the ground.

“Nine-Tailed, your strength is too strong. You need to be fried…”

Nine-Tailed, “?”

“What Jinchuriki are you exactly?”