I guess the school swimsuits have been around long enough (1950s apparently) that Mako's grandmother could have worn one.
Reizei-san's Swimsuit
G
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?
Drip...Drip...I used to be a flashy swimsuit gal myself you knowGranny was?Here's a picture of me when I was youngerI-Is that you, Granny?This is how you used to be, Gra- ......I'm...
not really your grandchild, am I Granny ......?What's got into you !?