"Treat Yourself" Rude Mushroom Birthday Card - Funny Square Design for Adults Only with Matching Envelope - Perfect for 18+ Birthday Celebrations

Looking for a cheeky birthday card for someone 18 or older?

This funny square card features a naked cartoon mushroom — high, frosted, and living their best life. Because sometimes, “treat yourself” means exactly that.

Perfect for anyone with a bold sense of humor!

Card Features:



• Square card with matching square envelope
• Envelope features a blue inner lining for an extra pop of fun
• Printed on high-quality cardstock
• Blank inside for your personal message
• Great for adult birthdays and guaranteed laughs

Customisation Options:

Want to change the quote? You can personalise it to make it more unique — or just as cheeky as you like!

• Add a custom quote at the top or bottom (max 10 words)
• Add quotes to both top and bottom (max 20 words total)
• Or select No Change to keep the original funny quote:"Naked, high, and covered in frosting... pretty sure this is what they meant by ‘treat yourself.’"

Important: Leave your custom quote in the order notes at checkout if choosing a personalised option.

Note: 18+ only – this card contains adult humor and is for mature buyers.

Make them laugh out loud on their birthday — they’ll never forget this one!