I would like to add something about characters.
It doesn't really matter how "original" they are (as almost any archetypical type of person has been drawn already), as long as they are believable characters. Sure thay can be a princess or super-heroine, as long as you give them an original reason to be that way. Give them a history and context to exist in. These do not have to be explained, or written about, but can be suggested visually (as my scenario-writing teacher told us: "Don't tell them, SHOW them").
Practically, you could do this with details, clothing, accessories, scenery, landscapes,... anything visually that would suggest a background.
Take for example my own Inquisitress Kitzalia. A female inquisitress is nothing new as an idea, but instead of setting her into a manga-ish fantasy setting, I chose to give her a place in the dark, muddy, Flemish medieval times. I mixed local history with my own imagination, and am quite happy with the result.
Concerning story/fetish content... From experience I have learned that you got to have a decent amount of fetish content (in this case: tickling) in your comic, in case you want to go commercial. People are paying to see tickling action, after all, if they would just be content with a good story they'd buy a mainstream comic instead. So, commercially speaking, I'd say basicly: the more tickling, the better.
Of course, if there's no room for story anymore, the tickling and the characters lose their reason to exist, and thus lose their credability. So at least some pages (or a good amount of single comic panels mixed through it) should be devoted exclusively into the storyline. If by any chance should you be able to sneak some tickling into a "story panel" (or "story page") by all means do so, it will help create some feel of continuity.
It's up to you to find a good balance between the two.
About adult content... If you feel up to it, I'd say go for it. For many people, tickling is a fetish (in a sexual way) and they will appreciate some (or more) adult content. I myself like to include nudity and suggestive bondage and tickling in my artwork and have had good experiences with it.
Don't try to force yourself on this, just have it the way you like it, which goes for everything else I said as well. After all, it's your comic, and there's no strict formula to create a good or succesful comic.
I'm very interested to see more of your work, especially when you would venture into the world of comic drawing.
I wish you a lot of success!! 🙂
