Yes, there are multiple flights from Bangkok Intl to Tokushima for under ฿ 21,013. The cheapest flight booked recently is on ANA for just ฿ 19,062, but on average you can expect to pay ฿ 49,681.
There are no direct flights from Bangkok Intl to Tokushima, but Cheapflights can provide you with all the information you need to find the fastest route with the fewest stops.
A quick flight from Bangkok Intl to Tokushima can take about 8h 55m. ANA provides one of the quickest options available for as low as ฿ 19,063.
Flying on ANA is currently your cheapest option to Tokushima, with prices starting at ฿ 19,063.