One of the legitimate options is Shonen Jump. It has a good collection of manga and ensures you're accessing the content legally. Keep in mind that subscription models and content offerings can change over time.
Some of the relatively safe manga sites include MangaFox and MangaReader. They have a decent reputation for providing content without major security risks.
One popular site is Project Gutenberg. It has a collection of Japanese novels in translation. Another option is Aozora Bunko which offers a wide range of Japanese literature for free. You can also check out Amazon Kindle store, where you can find many Japanese novels both in their original language and in translation.