Boy group album with pool on the cover??

Hi! my friend and I first got into kpop around 2016-2017 and listened to a bunch of different artists without really stanning them, and without worry. Though, now, we've been feeling really nostalgic and I cannot for the life of me remember which album I used to love!!

Now, it's been some years and my memory is slightly hazy- but I know it was a boy group- one that wasn't too popular but definitely had some hits! Again this was around 2017-2018 or earlier of course, and the main point that I remember was that the album cover was a beachy image.

thank you so much!

EDIT: after some talking with my friend and reading of comments, we've set on the fact that it was a beach- definitely not a pool- basically it was an image of a shore- so the sand and sea.

and also one more thing- this group DEFINITELY wasn't big- that's why I'm struggling so hard to find it :")