Time to Save Paula
When you enter Jackie's Cafe, talk to everybody. One person will mention that there is a loud noise outside, so head back out to see what's up. You'll find Everdred on the floor surrounded by a crowd of onlookers. Talk to the man on the far right and he'll move if you give him something. Give him a food item that you can part with or buy a ticket from the Topolla Theater and give him that.
When you get by, talk to Everdred. He'll tell you that Monotoli stole the Mani Mani statue from him. Do what he says and check behind the counter inside Jackie's Cafe. There are three columns of bottles behind the counter. The place to check is the one on the farthest right. You'll know you got it because a text box will pop up that says "???". You will be transferred to the psychotic world of Moonside!
Neon Lights of Moonside
Moonside is one of the most bizarre places in all of EarthBound. Everything is backwards now, so when you answer "yes" you are really saying "no" and vice versa. You will be attacked by a little flame inside the Cafe, which is a Robo-Pump. It will throw a bomb at you after three turns, so make sure to kill it before then. Outside, you'll find many enemies, some of which are difficult to defeat. Just be sure to heal up when you need to and take them out as fast as possible. Especially watch out for the Enraged Fire Plug which can take out a lot of HP from both Ness and Jeff at the same time. Try to gain enough levels to be in the upper 30s if you can.
The only way to get around in Moonside is by talking to men that will warp you around. These men all look the same, so it can get very confusing, very fast. Talk to everyone around to hear some funny (and mostly incomprehensible) dialogue. Head to the east when you exit the Cafe and find the hotel. Remember this spot and heal here when you need to. Find the man wearing a suit outside of the hospital, and he will warp to the inside where you can revive fallen party members. Wander around and eventually you end up behind the Monotoli building. There is a sailor here who says he won't let you pass until he sees a man who has connected eyebrows and a golden tooth.
From the hospital, go west and you'll come upon two warp men. Talk to one of them and he'll warp you to a new area. If you end up in the same open area you were just wandering around in, you chose the wrong one. Head back and pick the other. You will end up in a new part of the city unaccessible before. Here you follow a series of warps to different areas and will be able to pick up items along the way. Follow the warps and you'll enter a strange room with a man who looks like Mr. T.
Look carefully at around and you'll see another person in the room that looks like a shadow. Talk to him and answer him. Remember that "yes" and "no" are swapped in Moonside, so answer "no". Talk to Mr. T and he'll kick you out and into the hotel and the shadowy man will follow. He'll continually talk to you, and eventually you'll find out that he has connected eyebrows and a gold tooth! Take him to the man beside the Monotoli building to the south and they'll walk off together.
Talk to Monotoli in front of his building and he'll leave you with the Mani Mani statue. Restore you HP and PP completely before examining the statue.
When you defeat the statue, you'll end up in the storage room of Jackie's Cafe, with the broken statue right beside you. Talk to the mouse if you'd like and leave the Cafe.