Dear Shilpa,
Understanding the Basis for Engagement
Requirement is the basis for the engagement of the services of a person for hire. If we apply this analogy to all types of hiring, there would be no necessity for employment contracts and employment laws as well.
Approaching the Matter with a Broader Perspective
We have to approach the matter with a broader perspective and in terms of social justice. When the requirement is perennial in nature, the hiring process results in the phenomenon of employment with the inseparable ingredients of the employer, the employee, and the contract of employment.
Integrating Office Roles into Regular Employment
As long as you have an exclusive office for your business/industrial activity, the post of an office boy or office assistant becomes an integral part of the office. Therefore, my suggestion would be to convert it into a regular post and appoint a suitable person under a contract of employment. Initially, you can go in for a fixed-term contract basis and later regularize the post.