Have Relationship Questions? Ask a Counselor for Answers ASAP
If the nature of the emails/texts is of sexual nature then you cannot tell his sexual preference at this time. You may want to clarify with him what does he mean by wanting to catch someone's eye. If he is flirting or being unfaithful in any way (and that would include internet sex etc) then you ought to confront him and see what is he expecting of your relationship. Favorite movies or tone of voice are not indicators of one's sexual orientation either.