Thanks everyone for concern and suggestions. The point is that I have a full-time job making and selling BDSM erotica- I can'r run a commercial Mastodon tumblr replacement, much though I'd like to. I just don't have time or money to do so. Plus it is not really the model to follow in a federated social network- running your own instance is easy, and everyone can follow you from everywhere. Try masto.host for help.