It was some animal, half-digested. Frank and Winston saw that and felt like vomiting. But they somehow manage not to do so,
"What the fuck was that thing? Awkkwww" Frank said, trying to forget what he just saw. Winston took a deep breath and avoided thinking about what happened. Snake turned back and walked inside, while Frank and Winston looked at each trying to avoid eye contact.
"Let's just get over with this shit," Winston said without looking at Frank.
Frank didn't say anything, just kept breathing loudly.