What should i say, the typical onzen ova, some fanservice, super predictable plot, swimsuits that disappear and the cliche monster.
Story: Garbage, if you liked that much the show, you probably will feel disappointed to see AGAIN the onzen+Swimsuit plot, that you have already seen several times in every "mcdonalds" anime, the lack of creativity...
Art: Same as main anime, same studio of course, some fanservice, curiously not explicit.
Character: Not development of any character, it's an Ova it's okay.
Enjoyment: Since this is my personal taste i will be very subjective; boring or just to chill.
Overall: 4/10 Thank you, but no thank you.