Well because behind story he must be good and honor husbands because if he die in 3 year he go to hell if he did good deed and maybe reincarnation with his wife in next life
I think because ox and horse faul didn't mess up his soul he only get 3 year why not 9 dead good year mean 10 or 15 year life long what he did with reincarnation and judge cheat Yuma law only didn't give him little more than 3 year that why he have to promise ma or he want prove her he will die in 3 year she didn't have married him he dont have enough time
he lives for more than 3 years for some reason
Read spoilers and after promising to only be with his wife, he married the other girl and I think their should be another girl he marries. The author is trying to make it seem alright when we saw how his first wife was against the marrying of a concubine but now the author is trying to make it seem like she is ok with it.
This manga really made me want to read since you rarely find historical manga (male main lead) that isn't a harem or where he is completely in love with one girl and not giving little signs to other girls and may marry them as concubines or the completely remove the romance and just throw one girl at the end.
They didn't write harem since they will just be throwing the girls in and the wife will be ok with even through everyone in the beginning was against having another wife or cheating.
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