If you intend to read this manga only for the advertised slapstick comedy/romance in the summary, feel free to start from Ch.5. However, if you enjoyed the writing of Kanojo, Okarishimasu and/or want to objectively evaluate the manga for yourself, please ignore this review and go ahead from Ch. 1. Reasons as to why you should skip will be vaguely described below:.
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The manga spends the first 4 chapters constructing backstories for the characters. However, it does so in an unrealistic and drama-inducing way that does not serve as [good] punchlines nor serious fleshing out of the characters. I understand that being "unrealistic" is part and parcel of the trope to provide good comedy, but in this case, it simply feels jarring and pointless. This may cause certain readers who start from the beginning to feel like the manga is ill-summarized even after reading 3 chapters. Furthermore, for all the exposition the mangaka tries to introduce, no significant information is actually conveyed. Readers can just as easily understand how the mangaka is trying to frame the main characters from Ch. 5 and the "plot points" scattered in the first 4 chapters seem either irrelevant or will require reintroduction much further into the story anyway.

Therefore, I would recommend new readers to skip the first 4 chapters because you can save yourself a potentially poor reading experience while not really losing out on any important information. Just get to the part when the manga actually delivers on what the summary promises and judge for yourself whether this character dynamic is for you.