Just looked at the chapter 8 raw that is available (8.1, 8.2)
Obviously, she couldn't even finish the job back then and stop MC from being born. The next raw should explain her actions that resulted in MC's dad's death, but I hope it explains the development into a bloodline (face card?) grudge.
About the vibe cut line, I was able to zoom in on a raw I found and it was パイプカット which jisho has listed as vasectomy.
The last page makes all the drama of the previous page just deflate since this 55 (56 at this point?) year old man is still playing around. What karma or heavenly punishment?
あまたつ - たつ immediately translated in my mind to dragon from too many fantasy games. The あま gets expanded in the description to あまかける, which plugged into online dictionaries becomes 天翔ける, to soar, but あま is a reading of 天. So you could translate あまたつ to "heaven dragon," but you could also leave it...