JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//cdn.rawgit.com/mrdoob/three.js/master/build/three.min.js"></script>

CSS

body {
	  margin: 0;
}

JavaScript

// 1owk3y "Direction of arrow seems to
//   roam around in unpredictable directions"
const makeArrowLookAt_1 = function(obj, position){
  const posVector = new THREE.Vector3().copy(position);
  const localVector = obj.worldToLocal(posVector);
  localVector.normalize(); 
  obj.children[0].rotation.x = localVector.x;
  obj.children[0].rotation.y = localVector.y;
  obj.children[0].rotation.z = localVector.z;
}

// Mugen87 "causes arrow to stare at 
//   different unrelated direction"
const makeArrowLookAt_2 = function(obj, position){
  obj.children[0].lookAt(position);
}



var camera, scene, renderer;
var geometry, material, boxFrom, boxTo;

init();


function init() {

    camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 0.01, 10 );
    camera.position.z = 1;

    scene = new THREE.Scene();

    geometry = new THREE.BoxGeometry( 0.2, 0.2, 0.2 );
    material = new THREE.MeshNormalMaterial();

   	boxFrom = new THREE.Mesh( geometry, material );
    boxFrom.position.set(-0.5, 0.2, -0.4);
    scene.add( boxFrom );
    boxTo = new THREE.Mesh( geometry, material );
    boxTo.position.set(0.5, -0.2, -0.4);
    scene.add( boxTo );
    
    const dir = new THREE.Vector3( 0, 0, 0 );
    const arrowPosition = new THREE.Vector3( 0, 0, 0 );
    const length = 0.4;
    const hex = 0xffff00;
    
		arrowHelper = new THREE.ArrowHelper( dir, arrowPosition, length, hex );
		boxFrom.add(arrowHelper);
    
    renderer = new THREE.WebGLRenderer( { antialias: true } );
    renderer.setSize( window.innerWidth, window.innerHeight );
    document.body.appendChild( renderer.domElement );

}



function animate() {

    requestAnimationFrame( animate );

    boxFrom.rotation.x += 0.01;
    boxFrom.rotation.y += 0.02;
    
    boxTo.rotation.x -= 0.01;
    boxTo.rotation.y -= 0.02;
		
    //makeArrowLookAt_1(boxFrom, boxTo.position)
    makeArrowLookAt_2(boxFrom, boxTo.position)
    
    renderer.render( scene, camera );

}

animate();