You could try publishing them on online literary platforms dedicated to Bengali literature. Some popular ones are [mention specific platforms if available].
You could try submitting to literary magazines like 'The London Magazine' or 'Granta'. They often accept short story submissions from new and established writers.
Some traditional publishing houses also accept fantasy short stories. You could look into submitting to smaller indie publishers that focus on the fantasy genre. Another option is to enter writing contests specifically for fantasy short stories. This can give your work exposure and potentially lead to publication opportunities.
You might consider publishing on adult-themed literary websites or platforms that specifically accept such content. But make sure to read their terms and conditions carefully.
There are also specific publishing houses that focus on short fiction. Research and find ones that accept submissions and offer payment. It might take some time and effort to find the right fit for your work.