S. 95 states, nothing is an offence by reason that it causes or that it is intended to cause, or that it is known to be likely to cause, any harm, if that harm is so slight that no person of ordinary sense and temper would complain of such harm.
This section is based on the maxim – de minimize non curate (the law takes no account of trifles)
A dips his pen in B’s ink and B prosecuted A for theft, A can take defence of S. 95.