Nakaba says you don't have to read Nanatsu to read the Mokushiroku series, but I completely disagree with that, anyone who hasn't read nanatsu no taizai won't know any of the clues Nakaba left, all the community theories only exist because of Nanatsu , who is Sin? We only theorize that it is Lancelot since we know him in Nanatsu no taizai, Sin is Rou? Same thing, we met him in Nanatsu, why did Arthur turn evil? Is he cath? Also featured in Nanatsu's series, the appearance of sins only impacts those who have seen Nanatsu, it just doesn't make sense to read mokushiroku if you haven't seen Nanatsu, as it is not a completely separate story but a direct continuation that has its connections based on previous series.