Since its launch in late 2022, ChatGPT has generated both excitement and concern among language professionals in applied linguistics. Although various organizations, publishers, and institutions have introduced guidelines to address this phenomenon, these topdown approaches often neglect the nuanced experiences and perspectives of L2 academic writing teachers and their students. This study aims to bridge this gap by centering on the experiences of one EFL writing teacher and two international students in an undergraduate academic writing course in an English medium program in a Thai private university. In this class, students engaged in writing, reading, and discussions about what it means to be an academic writer in the age of generative AI. By employing collaborative poetic autoethnography, we argue that ChatGPT is more than just a tool or assistant; it has become a ubiquitous "ghostwriter" that requires careful navigation. Drawing on the poems, reflections, freewriting samples, and drafts collected from January to May 2024, the present study provides critical insights into ethical and effective integration of ChatGPT in EFL academic writing classes. The study also contributes to the domain of digital applied linguistics through depicting the opportunities and challenges presented by AI technologies in language and literacy education.