Pros
If you're truly desperate to find a job and need to address your work visa situation, this could be your last resort. However, be aware that the boss may terminate your employment at any time without any valid reason. Both hiring and firing decisions are solely at her discretion and can be made impulsively.
Kontras
In addition to the lack of any benefits, extremely low pay with the heavy workload, and no room for growth like other people says, the most toxic aspect of this company is the CEO's tacit approval or even support of office politics, which results in a highly unfriendly environment both among colleagues and behind the scenes. Besides dealing with a significant workload, there is also a substantial amount of time that needs to be devoted to handling office politics. If you are not adept at navigating office politics, I strongly advise you to carefully consider joining this company.