Error parsing a backslash in a simple Contact Form

Hi,
As per subject, I am parsing the "\" backslash character in my contact form.
The form works perfectly for anything other than a backslash.
If my Question field contains something like "Yes or No", then this will appear in the email correctly. However if the content says "yes\no" then it appears like this in the email:

yes\\\|||||/||/||/||y|e|s||||||||||||||/||/||/||||||||||||||||/||/||/

or something like this.

Is this a bug or is this a general PHP issue reading the backslash into a form.
Tried Googling this, not much to be found.
Tried the PHP String Replacer but I actually want the "\" to remain if possible so thats not an option here.

Hi mapme,

What's your email type ? Text or HTML ?

Please take a backup for your form and attach it here (if it has no private data) Or send it to me through the "Contact Us" Page and I will check it ASAP

Regards,
Max