After.cs

using System;
using System.Collections;
using UnityEngine;

public class After : MonoBehaviour
{
    static After _instance;
    static After instance
    {
        get
        {
            if ( _instance == null )
            {
                _instance = new GameObject( "After" ).AddComponent<After>();
                _instance.hideFlags = HideFlags.HideAndDontSave;
            }
            return _instance;
        }
    }

    public static Coroutine Delay( float time, Action action )
    {
        return instance.StartCoroutine( instance.DelayRoutine( time, action ) );
    }

    IEnumerator DelayRoutine( float time, Action action )
    {
        yield return new WaitForSeconds( time );
        action.Invoke();
    }
}