Romance manga w/ parent/guardian MCs

Elaine, disguising herself as an ugly girl to avoid troubles, took in a pair of twins at an especially dark night. Nonetheless, the twins' handsome dad caught up to her for his babies soon later and he started to doubt her intention, inquire into her past, and eye her with thorough contempt… finally triggering off hatred successfully.
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○ kids are 4 y/o
○ : infidelity (not between main couple), violence, kidnapping, murder, drugging, abuse

After years, Suk-O is thrilled to run into his high school crush, Suh-hee. The two have a one-night-stand, and when he wakes up he finds her baby in his bed and a note from Suh-hee saying she's sorry!
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○ child is an infant
○ : intercourse with one party drunk

Arcella, who lived a glorious life that everyone envied but died of illness at a young age. Before her death, she regretted not having become a proper mother to her son. But somehow, she went back three years ago. Arcella is living her second life. She vows to be a loving mother this time. However, is it too late?
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○ kid is 15 y/o
○ marriage of convenience

After dying in a car accident, a coroner wakes up in ancient China. After being attacked by a drugged man she unsuccessfully tried to treat, she bore a child and started crossdressing to get by.
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○ : drugged sex, gore