Girls bring a handbag on a date. Then you sit on the bench.
Now the question is where you put your handbag. If you like a guy, handbag should not be put between you and him. Handbag can be referred to as a wall. You do not want to intentionally build a wall. So in this case, if he is sitting on the right side, then you can put your bug on your left side.
In other words, if you do not like a person, make sure you put your handbag between you and him intentionally. By doing so, you are building a wall.
Please note that most of men probably do not think like “oh her handbag is here or there”. This is something we unconsciously feel. But if you remember this, this might be useful at some point.