Here is the webtoon on which the drama Amanza is based.

"Big See" by Kim Bo Tong.
A Lezhin comic.

Official link :
https://www.lezhin.com/en/comic/bigsee

Thank you for the link! Of course, it'll take me a VERY long time to dare to adventure into the webtoon considering how emotional it made me in just under 2.5 hours of story (the long credits at the end of each ep might tip it to or just past 2.5). Seeing this also means I have voices for the characters in my head to hear-emotional whiplash! I mean, I think the last thing that got my tears that "wide open hot water faucet with a broken handle" independently soaking me  was Mother w/Lee Bo Young-and like it (which is legitimately a 10/10 with no rounding up from 9.9, perfect as cinema can get), it is adapted from another and even moreso than Amanza I am too afraid of watching the original, especially knowing it's from Japan where most things are darker and more pain-filled/piercing than what Korea does with the same story-when they showcase human darkness, they jump into a proverbial/emotional black hole for those scenes!