Add oats and milk into a medium saucepan. Bring to a boil, reduce the heat to low, simmer uncovered for about 10 minutes (or if using quick/thin-rolled oats for about 3 minutes), stirring from time to time, until soft. At first, the oatmeal will be very thin but after adding the remaining ingredients and during cooling it will thicken significantly.
Remove the pot from the heat, add the peanut butter, coconut oil, maple syrup, lemon juice and a pinch of salt, stir until combined.
Stir in the mashed bananas, season to taste with more maple syrup and lemon juice if needed. The oatmeal should be sweet and sour, with a noticeable banana, peanut butter, and coconut flavor.
Divide equally between two bowls, sprinkle pomegranate seeds on top.