Daifuku is honest about what it is. There is no hidden fat, no cream, no oil. It is glutinous rice pounded into a shell at about 230 calories per 100g and red bean paste that is roughly half sugar by weight. One piece is 225 calories and 50g of carbs, which is the same carb load as a bowl of rice, in 3 bites. It does not feel like a bowl of rice. That is the whole problem.
The variations move the number less than you would think. Ichigo daifuku swaps some of the anko for a whole strawberry, so it lands around 190 despite being bigger. Mame daifuku with salted black beans is about 250 for a 110g piece. Kusa daifuku (mugwort) is the same as plain at about 220. The konbini versions are smaller, 70 to 80g, and run 170 to 190. The only real jump is the cream daifuku from the chiller, where whipped cream inside a mochi shell takes it to 260 with 10g of fat.
The place daifuku fits is after a protein meal, as the sweet thing, one piece. As a snack on its own it is a sugar spike with 4g of protein, and you are hungry again in an hour. Two with a canned coffee at the konbini is 550 calories and feels like nothing. The wagashi shop version is worth it. The konbini three pack is where the count goes wrong.