based on the labor code,

1. if an employee has continuously worked for an employer for a period of 6 months and 1 day, in absence of any contract/evidence of agreement, your friend is automatically considered under the law as a regular employee and hence, entitled to benefits mandated by the code.
2. he can claim benefits, if these are not provided by the employer first, by discussion with his employer, or seek assistance from department of labor- they will be more than willing.
3. the employer has still the right to hold his employee for a maximum of 30 days commencing from the submission of resignation letter even in the absence of the contract.

hope this helps