diff --git a/game/osu.py b/game/osu.py
index e915412..f2b454f 100644
--- a/game/osu.py
+++ b/game/osu.py
@@ -1,9 +1,61 @@
 import tkinter as tk
+import color
+
+class Circle:
+    def __init__(self, canvas: tk.Canvas, x, y, radius):
+        self.canvas = canvas
+        self.x = x
+        self.y = y
+        self.radius = radius
+        self.value = 9
+
+        self.circle_id = canvas.create_oval(x - radius, y - radius, x + radius, y + radius, outline = color.PURPLE, width = 2)
+        self.text_id = canvas.create_text(x, y, text = self.value, fill = color.PURPLE, font = (None, int(radius / 1.5)))
+
+    def delete(self):
+        self.canvas.delete(self.circle_id)
+        self.canvas.delete(self.text_id)
+
+    def decrement(self):
+        self.value -= 1
+        self.canvas.itemconfigure(self.text_id, text = self.value)
+
+    def isInside(self, x, y):
+        dx = x - self.x
+        dy = y - self.y
+        d = (dx**2 + dy**2)**0.5
+
+        return d <= self.radius
+
+canvas = None
+mouse_x = 0
+mouse_y = 0
+tick = 0
+circle = None
 
 # Main
-def main(canvas: tk.Canvas):
-    pass
+def main(c: tk.Canvas):
+    global canvas, circle
+
+    # Ini
+    canvas = c
+    c.bind('<Motion>', motion)
+
+    # Test
+    circle = Circle(c, 50, 50, 100)
+    circle.decrement()
 
 # Loop
 def loop(deltatime: float):
-    pass
+    global tick
+
+    print(circle.isInside(mouse_x, mouse_y))
+
+    tick += 1
+
+# Mouse
+def motion(event):
+    global mouse_x, mouse_y
+
+    mouse_x = event.x
+    mouse_y = event.y