Well lets see if I can remember.
Westside story episode 9
It starts off at Wang Xing's father's video shop where Aishen, Wang Xing and Beck are waiting for Aishens package to arrive. The "A06" robot. Aishen keeps going on and on about how great it is. Then his package finally arives and instead of a robot, there was a japanese girl in there. The three of them are puzzled as they thought that it would be a robot and they start poking it I mean her... Nevermind. Anyway, she says that she is so relieved to finally reach Tailand but the three of them explain that she is in Taiwan. (Poor thing) Aishen asked what happened to his 'A06' and the japanese girl explains that she threw away the robot so that she could go to Tailand. Aishen goes beserk and stuffs the girl back into the box and chased Beck and Wang Xing away when they tried to calm him down. He dragged the box all the way to an overhead bridge and wanted to throw her off but then he changed his mind. Aishen and Wang Xing brought the girl to a restaurant while Beck went shopping for clothes for the japanese girl. (Beck is a tomboy in case you don't know) And when she came back and gave the clothes to her to try, she came back and Aishen (And me ^_^) saw the most beautifull girl he(and I) have ever seen (My heart nearly stopped^_^) The three of them are determined to get her back to Japan but they don't have the money to buy tickets, so she would be going back the same way she came, but when they found out the price for sending a package, it was still expensive. The only way is for her to loose wait. (About 5kg) And she is already quite slim. Anyway Aishen, Wang Xing and Beck made the girl exersise and then Yuli (Meijie te si tai) and Yu Yayu came. Yuli thought that they were bullying the girl and tried to take her away but the girl went back to the trio. Yu Yayu asks them whats going on and they start explaining (They speed up the explaining part so their voices sound like chipmunks.) After explaining, (Yu Yayu and Yuli had the blur type of look on their face) Yu Yayu tells them to carry on. Well later in the show, the japanese girl goes out for a drink with Aishen and when she left to go to the restroom, Aishen took some of the sugar packets and put it into her orange juice. Later on, they also show Aishen fighting some gangsters who bullied an old man. (A genious and a fighter heh, cool) And well, I can't remember much of what happended after that.
Summary
Well, I can see that Aishen has fallen in love with the Japanese girl and he dosen't want her to leave. Thats why he put the sugar into her drink, so she wouldn't lose weight.