Both Aleph and Merlin have red, wavy hair that's shoulder length, 

The Idealist wears bandages wrapped all around his head that leave no traits out except for the lower half of his face, which uncovers a small scar near his lips and chin. 

Merlin as a doctor has a more pulchre but obscure look with long, 'ranchero' like clothes and a cloak, alongside red gloves. 

Aleph, as a prisoner has a similar look to The Idealist but less 'softer' and much more rugged, much like mental asylum patients.