If you have a winform with a background image then you would notice that the label background colour will not match the background so it will look like this.
NB: You can also use the properties to make the label Transparent. The Transparent option is available in the Web colors.
But you can easily do it in the code by this code
If you have a number of labels on the form then you can loop through each and make the background colour transparent.
Here is a code to make the background of the label as transparent.
For Each formLabel As Label In Me.Controls.OfType(Of Label)()
formLabel.BackColor = Color.Transparent