Responses
If you have a powerful gallery app that has a preset ratio, crop it to a 5:7 or 5:8 will do, otherwise doing it on PC might be easier though the resolution might be downed due to the browser, aside from that its very troublesome indeed
(Though sometime when Im too busy and cant crop Ill just open the full screen mode on the renta book reader and screenshot it whole so it ended up with the black margin on the top and the bottom)
ε=ε=(ノ≧∇≦)ノ

The chapter only costs 1$ but the true price is my soul when cropping screenshots