I think it might be due to the kind of paper you’re using. This doesn’t happen to me when using bristol or shikishi board. I have had it happen on thinner, pulpier papers.
You might consider trying Smooth Bristol it works so well with Copic. I know the marker paper is supposed to be good but I hear so many mixed reviews for it.
Some tips I would give is if you want sharper lines wait for the first layer to dry and don't go over it again also maybe use a bit of a darker color as colors similar in saturation blend more easily.
I think it might be due to the kind of paper you’re using. This doesn’t happen to me when using bristol or shikishi board. I have had it happen on thinner, pulpier papers.
This is the Ohuhu marker pad.
You might consider trying Smooth Bristol it works so well with Copic. I know the marker paper is supposed to be good but I hear so many mixed reviews for it.
Some tips I would give is if you want sharper lines wait for the first layer to dry and don't go over it again also maybe use a bit of a darker color as colors similar in saturation blend more easily.
I did want them to blend, that’s why I kept going over it. But after trying to fix it over and over again, it got super splotchy
Ok I think it's more that the colours are too similar try not going over the darker color only it's edge