Use XnViewMP (it's free) to rotate without any quality loss since it does not resave the jpeg, only tells the program opening a jpeg to rotate before showing it to you Install it and select all relevant jpegs by highlighting them Top menu bar "View" --> Lossless Jpeg Transformation --> Rotate clockwise
@b217285 They're being rotated by the image viewer because of the EXIF data, but the actual image, as seen in the gallery, isn't actually rotated properly. The ones in the gofile link are rotated properly.
It seems the e-hentai website viewer isn't taking the photo rotation data into account when displaying them. And even if you rotate them with a program losslessly without re-saving the jpeg (no quality loss), e-hentai doesn't care and displays them wrongly. The only way I think e-hentai will show them correctly is if the jpegs are resaved and lose their original quality with noisy re-compression artifacts. Or download the images and view them with any competent image viewer and it will render them correctly. Don't view through the website, view through an image viewing app and it will show up correctly.
@Scumbini I don't think they are rotated losslessly, the color is less vibrant and it looks like the picture shifted to the left, and the cropped pixels show up on the right. I viewed the pics with Qview and Windows Photoviewer.