C# Giving PictureBox the Shape of a String

Question

I want to make a PictureBox that containts a round picture and a string. The shape of the Box should not be rectangular, but adapted to the String and the round Picture. I need this for achieving "perfect" transparency, because apparently WindowsForms, when set to transparent, just lets through the picture of the parent box.

Here is the code that I made:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using System.Windows.Forms;
using System.Drawing;

namespace myProject
{
    class ShapedPictureBoxes : PictureBox
    {
        public ShapedPictureBoxes()
        {
            this.Paint += this.shapedPaint;
        }

    void shapedPaint(object sender, PaintEventArgs e)
    {
        System.Drawing.Drawing2D.GraphicsPath graphicsPath = new System.Drawing.Drawing2D.GraphicsPath();
        Rectangle rectangle = this.ClientRectangle;
        graphicsPath.AddEllipse(rectangle);
        graphicsPath.AddString(text, new FontFamily("Arial"), (int)System.Drawing.FontStyle.Bold, 14f, new Point(0,0), new StringFormat());

        e.Graphics.DrawString(text, new Font("Arial", 14f), Brushes.Red, new Point(0, 0));

        this.Region = new Region(graphicsPath);
    }

    public string text = "HERE COMES THE SUN";
}
}

When using this class and assigning a picture to it, this leads to strange behavior:

1. The text is not red, but white, there are some red particles in it, but mainly it is white. I assume that this comes from not identical Fonts. So how can I use the same font for both, the drawing and adding?
2. The text is white exept for there, where it lays above the image: there, it is transparent and you can see through the form.

How comes this and how can I fix it?

on the left side you see how it currently looks like, on the right side you see the two different pictureboxes next to each other.. I want it to look like on the left side, but with a readable RED text..