Measure and mix 100g of glutinous rice flour and 25g of granulated sugar in a large mixing bowl. Set the bowl aside for later use.
Wash and peel 4 peaches. Place the peach skins into a small saucepan and pour in ½ cup of water. Put the saucepan on the stovetop and bring the mixture to a boil over medium-high heat. Reduce heat to medium low, stir and let it simmer for about 5 minutes or until the water turns pink.
Set a fine mesh strainer over a small bowl, pour the mixture over the strainer to strain out the peach skins and collect the peach skin water in the bowl. While the peach skin water is still hot, measure and pour 80g of it into the bowl of glutinous rice flour and sugar. Stir the mixture with a pair of chopsticks until the water has been fully absorbed into the flour.
Use clean hands to knead the mixture into a smooth dough. You can add a little more of peach skin water if the dough feels too dry or fall apart.
Divide the dough into two portions, one larger and one smaller. The larger portion should be approximately 5 times the size of the smaller one. Use red food coloring to dye the larger dough into light pink, and dye the smaller dough into deeper pink.
Pinch off a small portion of the light pink dough, approximately 2.5g in weight, and shape it into a tiny ball by rolling it between your palms. Continue this process until all the light pink dough has been transformed into tiny balls. Be mindful that the dough may become dry over time. If it becomes too dry to shape, you can solve this by incorporating a small amount of peach skin water into the dough to restore its softness.
Use the deeper pink dough to make ears and noses for the piggy peach boba. Draw eyes with a black food coloring marker. Bring a pot of water to a boil. Boil piggy peach boba over medium heat for about 10 minutes or until floating.
Use a slotted spoon to transfer the cooked piggy peach boba to a large bowl filled with ice water.
Drain the water. Serve the piggy peach boba as a boba tea topping or dessert topping.