If you lose weight, it is also related to hari degree. When hari reaches a certain level, it will turn red. If it is full, it can't be reduced. So buy snacks. Snacks were bought at the grocery store after going out (I asked about Japan). Then the last icon in half a day can replenish energy to lose weight.
If you want to go to Rose House to lose weight, 12000 is quite cost-effective, and you can lose 3-4kg at a time.