[Review] Lost World.. My initial gacha-first experience..

Hmm.. First off, all the menus are in English, so I just skipped the story because it was too much of a hassle to read.. I guess I'm playing more for the illustrations than the story.. I saw a bunch of stuff in my mailbox and accepted it, and it turned out to be a lot of gacha currency, so.. I immediately did 3 x 10-pulls.. I just got a few 5-stars, so I was like 'Wow! 5-star!' and took screenshots.. Honestly, I have no idea what's good.. lol. What's weird is, where do you even use these 5-star backgrounds...?? Anyway, after pulling some cards and clearing the prologue, I got another copy of the bunny girl, so.. 1st constellation. Then I had a character upgrade ticket, so I gave the vampire girl another 1st constellation.. I was wondering how to level up? But then I realized you just level up by clearing stages, wow.. I thought it was the main stage after the prologue, but.. it was more story.. Korean patch please.. Reading English is such a pain.. Back to the characters.. It seems like you raise stats by consuming items... but seriously, what stats are we even raising..? And the party is set for 6 people, but it's a switching system, not front/back row.. I'm just playing on full auto attack, so as a newbie, I still have no clue what's what.