I do like her character and don't mind learning more about her but I feel this could have been done with a chapter long heartfelt conversation with Saotome to explain her actions at the end of the festive arc, not a multi-chapter flashback.
But let's be honest, anyone still reading this isn't here for plot or development, we know the latter is never happening, this is just about perving over busty high school girls and the flashback still has them.