Make it an object with a Collider set to Trigger. Then use OnTriggerEnter2D(Collider2D other) to detect when the character entered it, and deduct points.
public class Example : MonoBehaviour {
public float value;
private void OnTriggerEnter2D(Collider2D other) {
Player player = other.GetComponent<Player>();
if(player != null) {
player.points -= value;
}
}
}
So you need the player to move through and be detected, but it should also interact with the environment with physics?
One way would be to give the item one collider and one trigger, then in code use Physics2D.IgnoreCollision(itemCollider, playerCollider) when the item starts. You can give the item script a variable to get a reference to the collider. That way the trigger will still detect the player, but the collider will ignore the player.
You could also accomplish the same thing with physics layers and making the trigger a child object.