ProjectDDD/Assets/_DDD/_Scripts/BillBoardVisual.cs

using UnityEngine;

namespace DDD
{
    public class BillBoardVisual : MonoBehaviour
    {
        private Camera cam;

        void Start()
        {
            cam = Camera.main;
        }

        // Update is called once per frame
        void LateUpdate()
        {
            transform.localRotation = cam.transform.localRotation;
        }
    }
}