The present invention relates to a composition, preferably a cosmetic composition, and more preferably a skin cosmetic composition, comprising: (a) at least one complex, comprising at least one cationic polymer and at least one anionic polymer, at least one cationic polymer and at least one amphoteric polymer, at least one anionic polymer and at least one amphoteric polymer, or at least one amphoteric polymer, and at least one non-polymeric acid having two or more pKa values or salt(s) thereof or at least one non-polymeric base having two or more pKb values or salt(s) thereof; (b) at least one oil; and (c) water, wherein the cationic polymer comprises at least one cationic cellulose polymer with at least one fatty chain comprising at least 10 carbon atoms, and if the (a) complex comprises at least one anionic polymer and at least one amphoteric polymer, or at least one amphoteric polymer, the (a) complex further comprises at least one cationic cellulose polymer with at least one fatty chain comprising at least 10 carbon atoms. The composition according to the present invention is stable even at an elevated temperature, and can have a variety of cosmetic functions. For example, the composition according to the present invention can prepare a film which can have cosmetic effects such as moisturizing due to the oil(s).