Welcome to the real world! There are these things called rules, and standards. Part of being an adult is learning to adhere to rules, and having standards. I'm sorry if a story of yours/a story you read was taken down for not adhering to the rules or falling below this sites standards.
They have every right to remove material that violates terms of service, they are paying to maintain this domain which you get to use for free. I'm sorry if you don't understand the concept of a ToS, and that it has nothing to do with adult oriented material. The site literally says "Adult Fan fiction" Adult is a subjective term. Adult, can mean anything from graphic sex, graphic violence or extreme situations. Adult also varies by country, what is considered adult in the US is not the same as in the UK, EU Canada or Japan.
In closing, you should have read the Terms of service before posting, I know... reading is hard. But if you had you would have posted here, you wouldn't have wasted your time and I wouldn't be laughing at how juvenile your argument is. Seriously... are you 12? Even porn sites have rules for content.
TL:DR ... Learn 2 read ToS before signing up.