Steel, Guns, and the Industrial Party in Another World - Chapter 298:

Due to rejection of the heart donated by her ex-boyfriend, she married him and supported him with her own blood for two years. After the rejection disappeared, he unexpectedly filed for divorce. She readily agreed and left, revealing to him how he gotten the heart. When he learned the truth, he was furious and disgusted with her.Five years later, she pretended to be dead and returned with their child, disguised as an ugly nanny...

Kieran was just an ordinary part-timer — a high school dropout who had also given up on boxing. With no parents and no real family, he survived by working his ass off every day. He was raised by a man he believed to be his father, but later discovered he wasn't — though the man passed away before the truth could fully sink in. What Kieran didn’t know was that he was actually the sole heir to a powerful business empire, the hidden son of a wealthy tycoon.

Because I like to collect antiques, I was accidentally brought to a magical world by a crystal skull in my collection.

- Description from novelbuddy

Noda Sagiri is the only girl in her karate club, she has little feminine attributes but has a hidden talent in making sweets. On a whim she decided to bring her handmade cookies to her club, but after one of the idols of the school Michel François tasted her cookie he suddenly declared “I must meet with the girl who made these cookies!”. The search for the cookie maker began, however it seems that no one would come to expect that Sagiri is the one who made them….