I learned that if you font want people to be on an island with you, set up a tour but don't go do the tour, disabling any one from coming in the island. so I usually do this on the international island to get beetles early.
Anyway, bad experience time.
I met a guy on the island named Doug, now Doug was cool, he gave me bells, and even bought a wetsuit for me. We played a few tours, and I began to trust him enough to invite him to my town. At my town, two other CT friends dropped by, it was cool. And then suddenly Doug says he has to go. He says "read the bulletin board after I leave.". So I did what he said, and guess what I find...
"HAHA I STOLE YOUR BLUE FLOWERS JAKE, SUCK MY D!CK BECAUSE I'M DELETING YOU!"
I ran all the way to my blue rose zen garden that I was making, and guess what? THEIR ALL GONE.
I know it's only a game, but I legit cried for 5 minutes on my couch, I'm a dude too lol.
anyway, I've made like one CT friend since then, I almost never let someone out of my sight in my town now.