Does he receive any disability benefits, or have other 2016 income?
To claim a non-relative as a dependent they have to live in your home for a year. They cannot have gross income of $4,050 or more for the year.
A non-relative dependent is not eligible for EIC.
Your tax refund will not be seized for the debts of a dependent.
You may be able to claim him as a non-relative dependent if he meets all the requirements under the Qualifying Relative rules.
To be a Qualifying Relative -
1. The person cannot be your qualifying child or the qualifying child of any other taxpayer. A child is not the qualifying child of any other taxpayer if the child's parent (or any other person for whom the child is defined as a qualifying child) is not required to file an income tax return or files an income tax return only to get a refund on income tax withheld.
2. The person either (a) must be related to you or (b) must live with you all year as a member of your household.
3. The person's gross income for the year must be less than $4,050 (social security does not count) in 2016
4. You must provide more than half of the person's total support for the year.
5. The person must be a U.S. citizen or a U.S., Canada, or Mexico resident for some part of the year.
6. The person must not file a joint return with their spouse.
"they have to live in your home for a year." Just a clarification: He must have lived in your home the entire year of 2016.
Seems this boyfriend has become a husband, see <a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/3408380-can-i-file-head-of-household-and-claim-my-disable-husband-as-dependent-and-get-eic-for-him-and-since-he-owe-taxes-can-it-affect-my-refund">https://ttlc.intuit.com/questions/3408380-can-i-file-head-of-household-and-claim-my-disable-husband-as-dependent-and-get-eic-for-him-and-since-he-owe-taxes-can-it-affect-my-refund</a>