Don't look like the end of a bus

[English Freak]

On a bus, it read "Don't look like the end of a bus."
Could you please tell me the meaning?

 

[5jj]

Was there anything else to go with this?

Normally 'to look like the back end of a bus', or 'to have a face like the back end of a bus', means 'to look ugly'

 

[English Freak]

Thanks fivejedjon.
Actually, it was an ad on the bus. I'm not sure if there was anything else.